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Experimental Study On Force Measurement For AA 1100 Sheets Formed By Incremental Forming
Available online at www.sciencedirect.com
ScienceDirect Materials Today: Proceedings 18 (2019) 2738–2744
www.materialstoday.com/proceedings
ICMPC-2019
Experimental Study On Force Measurement For AA 1100 Sheets Formed By Incremental Forming Praveen kumar Ga*, Kurra Suresha
a
Department of Mechanical Engineering, BITS Pilani, Hyderabad Campus, India
Abstract Incremental Sheet Forming (ISF) has exhibited its high potential to form complex three-dimensional parts with simple tooling. The amount of force attaining on the forming tool is one of the important parameter in ISF process for tool design as well as failure prediction. This paper presents the experimental study on forming forces in single point incremental process of AA1100. A three channel strain gauge type force dynamometer with the incremental forming fixture on the top of it has been used for force measurement. The study was mainly focused on investigating the effect of step depth, tool diameter, wall angle and sheet thickness on forming forces. The results reveal that there exist a relationship between various process parameters and forming forces. The magnitude of plunge force in thickness direction of sheet is more compared to the forces in other two directions. The plunge force increasing rapidly during initial plunge of tool into the sheet and it remains almost study during entire forming operation. The thickness of blank has significant effect on the forming force, the results revealed that force has increased fourfold by increasing thickness from 1mm to 2mm. © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019 Keywords:Incremental forming; Formingforce; Process parameters
1. Introduction Incremental forming process has been distinguished as a financially feasible process for prototypes and low volume creation. The procedure is entirely adaptable and should be possible on a PC numerically controlled machines or specialized designed machines for ISF applications. In this process, a flat sheet metal is held in a specially designed fixture and is deformed into required shape by a hemispherical-ended tool.
* Corresponding author. Tel.: 9705801492 E-mail address: [email protected]
2214-7853© 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019
P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
2739
The way of the tool is controlled by a section program created utilizing computer aided manufacturing (CAM) programming. The principle appealing features of this process is easy tooling and better formability characteristics over the customary sheet metal forming processes. Kurra at el.(2014). A schematic representation of single point incremental forming process has been shown in Fig. 1(a-b). (b)
(a) Forming tool Clamping plate
Backing plate
Sheet Blank
Support
Bottom plate Fig. 1. Schematic representation of SPIF process (a) Schematic illustration of process (b) Sheet metal fixing device
The forming force is one of the prominent factors to design the fixture, forming tools and selection of machine tool. Duflou et al. (2007) reported that impact of different process parameters on forming force by Al 3003 - O with different sheet thicknesses on incremental sheet forming. The Forming forces were measured using Kistler model no. 9265B six-segment force dynamometer. Bagudanch et al. (2013) demonstrated that the extant at which forming force varied with a variation in the bending condition. They also suggested as the spindle speed increases the forming forces were decreased. Jeswiet et al.(2005) measured forming forces all three directions (axial direction radial and tangential) using spindle mounted force sensor, they formed using aa3003-0 material with conical and pyramid geometries. They observed from experimental results peak force raises while forming wall angle 60º. Ambrogio et al. (2006) concluded that the calculating the force gradient can be used as a preventing failure in incremental forming process. Fiorentino et al. (2012) and Filice et al. (2006) used real time force data to detect the fracture during forming. Petek et al. (2009) developed for on line autonomous system for fracture detection based on line force data. Centeno et al. (2014) examined the impact of axial forming forces on AISI304 stainless steel sheets of different spindle speeds in incremental forming process. They observed that spindle speed important role reducing the vertical forming force. Khalid A et al. (2014) conducted study on plunge forces in incremental sheet forming of a geometry with corner feature using response surface approach. It was observed that the corner geometry feature requires more force than the wall. Liu et al. (2014) analyzing the forming forces on various wall angles, sheet thickness, step down sizes and sheet orientation. Experimental results revealed that vertical plunge force increases with increase in step depth as well as increase in the sheet thickness. Also they observed minimum vertical force while forming the sheet at 450. Arfa, et al. (2012) examined effect of helical tool path way as to creating truncated shape on aluminum sheets by experimental and simulation using ABAQUS software. They observed that the load exerted by tool was more stable for helical tool path. Bansal et al. (2017) proposed analytical model to predict the formed component thickness, contact area and forming forces during single stage as well as multi stage incremental forming. Duflou et al. (2007) investigated experimental study on forming forces using face central composite design of experiments for al 3003-0 material. They found second order regression expressions to calculate forming forces based proces parameters (step depth, tool diameter, wall angle and sheet thickness). Saidiet al. (2015) Experimental study on forces in incremental sheet forming using two materials one being austenitic stainless steel (ASS304 L) and other was aluminium alloy AA1050 with various process parameters. They observed that an increase of process parameters (thickness of sheet, wall angle, step depth) breaking strength of material in an in increase in the Fz force.
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P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
Also the experimental results are compared with FEM simulations. Durante et al. (2009) and Kumar et al. (2018) demonstrated that Prediction of forming forces in ISF is important in order to ensure the safe utilization of the hardware and adapted machinery. Aerens et al. (2010) derived equation for predicting the forming force as a function of tensile strength of material, tool diameter, sheet thickness, wall angle and scallop height. The applicability of Eq. 1 for different geometries with Variable Wall Angle (VWA) components has been validated by published works of Bagudanch et al. (2011) & Perez-Santiago et al. (2011).
FZS 0.0716 Rmt01.57 dt0.41 h0.09 cos
(1)
Where Rm is the ultimate tensile strength, tois the initial sheet thickness, dt is the tool diameter, α is the initial wall angle and ∆h is the scallop height. Aerens et al. (2010) also proposed the accompanying approximation.
Z 2 . sinα. h. dt h 2.sin . h.dt
(2)
Li et al.(2015) examined impact of process parameters on consumed energy during the forming process and also they proposed optimal conditions for higher geometric accuracy. The deformation energy during the incremental forming process was calculated based on the measured forming forces. Ingarao et al. [12] examined the measured force data to Calculate the energy consumption required for the incremental sheet forming process, 2. Experimental set up and tested material Experiments are performed on a Bridgeport 3 axis CNC milling machine as shown in Fig. 2. Sheet metal is clamped between the two fixtures such that no material flows from the forming area. The forming forces are measured using EMIT CNC milling tool dynamometer in which strain gauges are mounted to sense milling force in 3 principle directions X- Y- Z independently. Forces are recorded using EMIT data acquisition system with 10000 samples per sec. which is connected through USB. The parameters used for this experiments varied tool diameters ( 5mm, 10mm & 15mm), step depth (0.25, 0.75 & 1.25 mm) & wall angle of ( 30º, 50º& 70º). The feed rate was 1000 mm/ min. All the test ware conducted using AA 1100 sheet blank with thickness of 1mm and 2mm and blank size is 250 x 250 mm2. The geometry used for this work was D-shaped model as shown in Fig. 2 (a-b).
Fig. 2a. Geometry of the part formed for the analysis of forces
P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
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Fig. 2 b. Forming operation performed on work piece
3. Experimental results and discussion 3.1 Influence of tool diameter Fig. 3 (a-b) shows axial forming force curves for the incremental formed parts with varying tool diameter 5 mm, 10 mm & 15 mm. The process parameters used as step depth 0.75 mm, wall angle 50º and 1 mm sheet thickness. It is observed that as increase in tool diameter forces were increased gradually, because of larger area contact between blank and tool interface that leads to larger material formed at that point. This is one of the limitation for hardware and adopted machinery used for incremental forming process. Fig. 4a represents force curves for FX, FY & FZ obtained at wall angle 50º. FZ starts at zero initially then quickly increase a level then it remains study state during entire forming operation. It is noticed that the axial force (FZ ) has greater magnitude force component compared to other lateral forces (FX & FY ) so it can be can be considered as more prominent force for design or selection of on incremental forming set up.
Fig. 3 (a). Force curves for parts formed with tools 5mm, 10mm & 15 mm diameter
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P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
º
Fig. 3 (b). Measured force curves for part 50 wall angle 5 mm tool diameter 1mm thick sheet
3.2 Influence of step depth Fig. 4 & Fig. 5 shows the experimental results parts formed with varying step depth 0.25 mm, 0.75 mm & 1.25 mm. It is clear that axial forming force increased with increase in vertical step depth, because material accessible for local deformation is increased at that point. That is, force directly proportional to step size. Fig. 4 shows forces curves for using 5 mm tool diameter, 1 mm thick sheet at 50º wall angle, similarly Fig. 5 shows force curves for using 15 mm tool diameter, 2 mm thick sheet at same wall angle.
Fig. 4. Variation of force with increasing vertical step size
Fig. 5. Variation of force with increasing vertical step size
3.3 Influence of Wall angle The trend of wall angle also a important factor for forming forces. D -shaped model formed on CNC milling machine using AA 1100 material with starting angle 30º to final angle 70º with an increment of 20º. The tool diameter is 15 mm & step depth 0.75 mm. The resultant magnitude of forces is showed in Fig. 6. As the part wall angle increases the magnitude of forming force increases gradually, due to larger lateral area of tool tip touches the blank. Therefore, contact zone at the blank and tool interface is larger for local deformation.
P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
2743
Fig. 6. Force curves for parts using 15 mm tool diameter 0.75 mm step depth with 300, 500 & 70◦wall angle
3.4 Influence of sheet thickness Fig. 7 shows the resultant forces for parts with 50º wall angle, 15 mm tool diameter, 0.75 mm step depth formed by using 1mm and 2mm thick AA 1100. As sheet thickness increases the forming forces increases due to more material formed during each pass of the forming operation, which required higher forming force to form a require shape. The magnitude of force rises up to 2370 N for 2mm thick sheet formed at 50º wall angle, while it is 608 N for a 1mm sheet at the same angle.
Fig. 7. Force curves for parts formed using 1mm and 2mmthick AA 1100
4. Conclusions Forces are measured for incremental formed parts using various process parameters tool diameter, vertical step size, wall angle and sheet thickness. Following conclusions are drawn from experimental study. 1. 2. 3. 4.
As the tool diameter increases from 5 mm to 15 mm. Axial forming forces increases 250N, 300N, 350N accordingly due to increasing contact area between tool and sheet blank. Increasing step depth (0.25mm, 0.75mm, & 1.25mm) the forming forces increase gradually up to certain values due to bending mechanics, stretching mechanics exists and force trends vary due to thinning and strain hardening. As increasing wall angle from 30º to 70º the forming forces increases accordingly because higher later area of tool tip touches the sheet blank. Sheet thickness is important factor for forming forces. As increase in sheet thickness from 1mm to 2mm, the forming forces increased four times as initial thickness.
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P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
References [1]. [2]. [3]. [4]. [5]. [6]. [7]. [8]. [9]. [10]. [11]. [12]. [13]. [14]. [15]. [16]. [17]. [18]. [19]. [20]. [21]. [22]. [23]. [24].
Aerens R, Eyckens P, Van Bael A, Duflou JR. The International Journal of Advanced Manufacturing Technology. 46 (2010) 969-982. Al-Ghamdi KA, Hussain G.The International Journal of Advanced Manufacturing Technology. 76 (2015) 2185-2197. Ambrogio G, Filice L, Micari F. Journal of materials processing technology. 177 (2006) 413-416. Arfa H, Bahloul R, BelHadjSalah H. International journal of material forming. 6(4) (2013) 483-510. Bagudanch I, Centeno G, Vallellano C, Garcia-Romeu ML. Procedia Engineering. 63 (2013) 354-360. Bagudanch I, Perez-Santiago R, Garica-Romeu ML, Rodríguez C. Proceedings of 10th International Conference of Technology of Plasticity (2011) 541-546. Bahloul R, Arfa H, BelHadjSalah H. The International Journal of Advanced Manufacturing Technology. 74 (2014)163-185. Bansal A, Lingam R, Yadav SK, Reddy NV. Journal of Manufacturing Processes. 28 (2017) 486-493. Centeno G, Bagudanch I, Martínez-Donaire AJ, Garcia-Romeu ML, Vallellano C. Materials & Design. 63 (2014) 20-29. Duflou J, Tunckol Y, Szekeres A, Vanherck P. Journal of Materials Processing Technology. 189 ( 2007 ) 65-72. Duflou JR, Tunckol Y, Aerens R. Key Engineering Materials 344 (2007 ) 543-550. Durante M, Formisano A, Langella A, Minutolo FM. Journal of Materials Processing Technology.209 (9) ( 2009 ) 4621-4626. Fiorentino A. The International Journal of Advanced Manufacturing Technology. 68(2013) 557-563. Filice L, Ambrogio G, Micari F. CIRP annals-Manufacturing technology. 55 (1) (2006) 245-248. Ingarao G, Ambrogio G, Gagliardi F, Di Lorenzo R. Journal of Cleaner Production. 29 (2012) 255-268. Jeswiet J, Duflou JR, Szekeres A. Trans Tech Publications.6 (2005) 449-456. Kurra S, Regalla SP. Journal of Materials Research and Technology.3(2) (2014) 158-171. Kumar A, Gulati V. Sādhanā. 43 (10) (2018) 159 (1-15). Liu Z, Li Y, Meehan PA. International Journal of Precision Engineering and Manufacturing. 14(11 )2013 1891-1899. Li Y, Liu Z, Lu H, Daniel WB, Liu S, Meehan PA. The International Journal of Advanced Manufacturing Technology. 73 (2014) 571-587. Li Y, Lu H, Daniel WJ, Meehan PA. The International Journal of Advanced Manufacturing Technology. 79 (2015) 2041-2055. Saidi B, Boulila A, Ayadi M, Nasri R. Mechanics & Industry. 16 (2015);410(1-5) Petek A, Kuzman K, Suhač B. CIRP annals. 58(1) (2009) 283-286. Pérez-Santiago R, Bagudanch I, García-Romeu ML. Key Engineering Materials. 473 (2011) 833-840.
ScienceDirect Materials Today: Proceedings 18 (2019) 2738–2744
www.materialstoday.com/proceedings
ICMPC-2019
Experimental Study On Force Measurement For AA 1100 Sheets Formed By Incremental Forming Praveen kumar Ga*, Kurra Suresha
a
Department of Mechanical Engineering, BITS Pilani, Hyderabad Campus, India
Abstract Incremental Sheet Forming (ISF) has exhibited its high potential to form complex three-dimensional parts with simple tooling. The amount of force attaining on the forming tool is one of the important parameter in ISF process for tool design as well as failure prediction. This paper presents the experimental study on forming forces in single point incremental process of AA1100. A three channel strain gauge type force dynamometer with the incremental forming fixture on the top of it has been used for force measurement. The study was mainly focused on investigating the effect of step depth, tool diameter, wall angle and sheet thickness on forming forces. The results reveal that there exist a relationship between various process parameters and forming forces. The magnitude of plunge force in thickness direction of sheet is more compared to the forces in other two directions. The plunge force increasing rapidly during initial plunge of tool into the sheet and it remains almost study during entire forming operation. The thickness of blank has significant effect on the forming force, the results revealed that force has increased fourfold by increasing thickness from 1mm to 2mm. © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019 Keywords:Incremental forming; Formingforce; Process parameters
1. Introduction Incremental forming process has been distinguished as a financially feasible process for prototypes and low volume creation. The procedure is entirely adaptable and should be possible on a PC numerically controlled machines or specialized designed machines for ISF applications. In this process, a flat sheet metal is held in a specially designed fixture and is deformed into required shape by a hemispherical-ended tool.
* Corresponding author. Tel.: 9705801492 E-mail address: [email protected]
2214-7853© 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019
P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
2739
The way of the tool is controlled by a section program created utilizing computer aided manufacturing (CAM) programming. The principle appealing features of this process is easy tooling and better formability characteristics over the customary sheet metal forming processes. Kurra at el.(2014). A schematic representation of single point incremental forming process has been shown in Fig. 1(a-b). (b)
(a) Forming tool Clamping plate
Backing plate
Sheet Blank
Support
Bottom plate Fig. 1. Schematic representation of SPIF process (a) Schematic illustration of process (b) Sheet metal fixing device
The forming force is one of the prominent factors to design the fixture, forming tools and selection of machine tool. Duflou et al. (2007) reported that impact of different process parameters on forming force by Al 3003 - O with different sheet thicknesses on incremental sheet forming. The Forming forces were measured using Kistler model no. 9265B six-segment force dynamometer. Bagudanch et al. (2013) demonstrated that the extant at which forming force varied with a variation in the bending condition. They also suggested as the spindle speed increases the forming forces were decreased. Jeswiet et al.(2005) measured forming forces all three directions (axial direction radial and tangential) using spindle mounted force sensor, they formed using aa3003-0 material with conical and pyramid geometries. They observed from experimental results peak force raises while forming wall angle 60º. Ambrogio et al. (2006) concluded that the calculating the force gradient can be used as a preventing failure in incremental forming process. Fiorentino et al. (2012) and Filice et al. (2006) used real time force data to detect the fracture during forming. Petek et al. (2009) developed for on line autonomous system for fracture detection based on line force data. Centeno et al. (2014) examined the impact of axial forming forces on AISI304 stainless steel sheets of different spindle speeds in incremental forming process. They observed that spindle speed important role reducing the vertical forming force. Khalid A et al. (2014) conducted study on plunge forces in incremental sheet forming of a geometry with corner feature using response surface approach. It was observed that the corner geometry feature requires more force than the wall. Liu et al. (2014) analyzing the forming forces on various wall angles, sheet thickness, step down sizes and sheet orientation. Experimental results revealed that vertical plunge force increases with increase in step depth as well as increase in the sheet thickness. Also they observed minimum vertical force while forming the sheet at 450. Arfa, et al. (2012) examined effect of helical tool path way as to creating truncated shape on aluminum sheets by experimental and simulation using ABAQUS software. They observed that the load exerted by tool was more stable for helical tool path. Bansal et al. (2017) proposed analytical model to predict the formed component thickness, contact area and forming forces during single stage as well as multi stage incremental forming. Duflou et al. (2007) investigated experimental study on forming forces using face central composite design of experiments for al 3003-0 material. They found second order regression expressions to calculate forming forces based proces parameters (step depth, tool diameter, wall angle and sheet thickness). Saidiet al. (2015) Experimental study on forces in incremental sheet forming using two materials one being austenitic stainless steel (ASS304 L) and other was aluminium alloy AA1050 with various process parameters. They observed that an increase of process parameters (thickness of sheet, wall angle, step depth) breaking strength of material in an in increase in the Fz force.
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P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
Also the experimental results are compared with FEM simulations. Durante et al. (2009) and Kumar et al. (2018) demonstrated that Prediction of forming forces in ISF is important in order to ensure the safe utilization of the hardware and adapted machinery. Aerens et al. (2010) derived equation for predicting the forming force as a function of tensile strength of material, tool diameter, sheet thickness, wall angle and scallop height. The applicability of Eq. 1 for different geometries with Variable Wall Angle (VWA) components has been validated by published works of Bagudanch et al. (2011) & Perez-Santiago et al. (2011).
FZS 0.0716 Rmt01.57 dt0.41 h0.09 cos
(1)
Where Rm is the ultimate tensile strength, tois the initial sheet thickness, dt is the tool diameter, α is the initial wall angle and ∆h is the scallop height. Aerens et al. (2010) also proposed the accompanying approximation.
Z 2 . sinα. h. dt h 2.sin . h.dt
(2)
Li et al.(2015) examined impact of process parameters on consumed energy during the forming process and also they proposed optimal conditions for higher geometric accuracy. The deformation energy during the incremental forming process was calculated based on the measured forming forces. Ingarao et al. [12] examined the measured force data to Calculate the energy consumption required for the incremental sheet forming process, 2. Experimental set up and tested material Experiments are performed on a Bridgeport 3 axis CNC milling machine as shown in Fig. 2. Sheet metal is clamped between the two fixtures such that no material flows from the forming area. The forming forces are measured using EMIT CNC milling tool dynamometer in which strain gauges are mounted to sense milling force in 3 principle directions X- Y- Z independently. Forces are recorded using EMIT data acquisition system with 10000 samples per sec. which is connected through USB. The parameters used for this experiments varied tool diameters ( 5mm, 10mm & 15mm), step depth (0.25, 0.75 & 1.25 mm) & wall angle of ( 30º, 50º& 70º). The feed rate was 1000 mm/ min. All the test ware conducted using AA 1100 sheet blank with thickness of 1mm and 2mm and blank size is 250 x 250 mm2. The geometry used for this work was D-shaped model as shown in Fig. 2 (a-b).
Fig. 2a. Geometry of the part formed for the analysis of forces
P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
2741
Fig. 2 b. Forming operation performed on work piece
3. Experimental results and discussion 3.1 Influence of tool diameter Fig. 3 (a-b) shows axial forming force curves for the incremental formed parts with varying tool diameter 5 mm, 10 mm & 15 mm. The process parameters used as step depth 0.75 mm, wall angle 50º and 1 mm sheet thickness. It is observed that as increase in tool diameter forces were increased gradually, because of larger area contact between blank and tool interface that leads to larger material formed at that point. This is one of the limitation for hardware and adopted machinery used for incremental forming process. Fig. 4a represents force curves for FX, FY & FZ obtained at wall angle 50º. FZ starts at zero initially then quickly increase a level then it remains study state during entire forming operation. It is noticed that the axial force (FZ ) has greater magnitude force component compared to other lateral forces (FX & FY ) so it can be can be considered as more prominent force for design or selection of on incremental forming set up.
Fig. 3 (a). Force curves for parts formed with tools 5mm, 10mm & 15 mm diameter
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P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
º
Fig. 3 (b). Measured force curves for part 50 wall angle 5 mm tool diameter 1mm thick sheet
3.2 Influence of step depth Fig. 4 & Fig. 5 shows the experimental results parts formed with varying step depth 0.25 mm, 0.75 mm & 1.25 mm. It is clear that axial forming force increased with increase in vertical step depth, because material accessible for local deformation is increased at that point. That is, force directly proportional to step size. Fig. 4 shows forces curves for using 5 mm tool diameter, 1 mm thick sheet at 50º wall angle, similarly Fig. 5 shows force curves for using 15 mm tool diameter, 2 mm thick sheet at same wall angle.
Fig. 4. Variation of force with increasing vertical step size
Fig. 5. Variation of force with increasing vertical step size
3.3 Influence of Wall angle The trend of wall angle also a important factor for forming forces. D -shaped model formed on CNC milling machine using AA 1100 material with starting angle 30º to final angle 70º with an increment of 20º. The tool diameter is 15 mm & step depth 0.75 mm. The resultant magnitude of forces is showed in Fig. 6. As the part wall angle increases the magnitude of forming force increases gradually, due to larger lateral area of tool tip touches the blank. Therefore, contact zone at the blank and tool interface is larger for local deformation.
P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
2743
Fig. 6. Force curves for parts using 15 mm tool diameter 0.75 mm step depth with 300, 500 & 70◦wall angle
3.4 Influence of sheet thickness Fig. 7 shows the resultant forces for parts with 50º wall angle, 15 mm tool diameter, 0.75 mm step depth formed by using 1mm and 2mm thick AA 1100. As sheet thickness increases the forming forces increases due to more material formed during each pass of the forming operation, which required higher forming force to form a require shape. The magnitude of force rises up to 2370 N for 2mm thick sheet formed at 50º wall angle, while it is 608 N for a 1mm sheet at the same angle.
Fig. 7. Force curves for parts formed using 1mm and 2mmthick AA 1100
4. Conclusions Forces are measured for incremental formed parts using various process parameters tool diameter, vertical step size, wall angle and sheet thickness. Following conclusions are drawn from experimental study. 1. 2. 3. 4.
As the tool diameter increases from 5 mm to 15 mm. Axial forming forces increases 250N, 300N, 350N accordingly due to increasing contact area between tool and sheet blank. Increasing step depth (0.25mm, 0.75mm, & 1.25mm) the forming forces increase gradually up to certain values due to bending mechanics, stretching mechanics exists and force trends vary due to thinning and strain hardening. As increasing wall angle from 30º to 70º the forming forces increases accordingly because higher later area of tool tip touches the sheet blank. Sheet thickness is important factor for forming forces. As increase in sheet thickness from 1mm to 2mm, the forming forces increased four times as initial thickness.
2744
P. Kumar G and K. Suresh / Materials Today: Proceedings 18 (2019) 2738–2744
References [1]. [2]. [3]. [4]. [5]. [6]. [7]. [8]. [9]. [10]. [11]. [12]. [13]. [14]. [15]. [16]. [17]. [18]. [19]. [20]. [21]. [22]. [23]. [24].
Aerens R, Eyckens P, Van Bael A, Duflou JR. The International Journal of Advanced Manufacturing Technology. 46 (2010) 969-982. Al-Ghamdi KA, Hussain G.The International Journal of Advanced Manufacturing Technology. 76 (2015) 2185-2197. Ambrogio G, Filice L, Micari F. Journal of materials processing technology. 177 (2006) 413-416. Arfa H, Bahloul R, BelHadjSalah H. International journal of material forming. 6(4) (2013) 483-510. Bagudanch I, Centeno G, Vallellano C, Garcia-Romeu ML. Procedia Engineering. 63 (2013) 354-360. Bagudanch I, Perez-Santiago R, Garica-Romeu ML, Rodríguez C. Proceedings of 10th International Conference of Technology of Plasticity (2011) 541-546. Bahloul R, Arfa H, BelHadjSalah H. The International Journal of Advanced Manufacturing Technology. 74 (2014)163-185. Bansal A, Lingam R, Yadav SK, Reddy NV. Journal of Manufacturing Processes. 28 (2017) 486-493. Centeno G, Bagudanch I, Martínez-Donaire AJ, Garcia-Romeu ML, Vallellano C. Materials & Design. 63 (2014) 20-29. Duflou J, Tunckol Y, Szekeres A, Vanherck P. Journal of Materials Processing Technology. 189 ( 2007 ) 65-72. Duflou JR, Tunckol Y, Aerens R. Key Engineering Materials 344 (2007 ) 543-550. Durante M, Formisano A, Langella A, Minutolo FM. Journal of Materials Processing Technology.209 (9) ( 2009 ) 4621-4626. Fiorentino A. The International Journal of Advanced Manufacturing Technology. 68(2013) 557-563. Filice L, Ambrogio G, Micari F. CIRP annals-Manufacturing technology. 55 (1) (2006) 245-248. Ingarao G, Ambrogio G, Gagliardi F, Di Lorenzo R. Journal of Cleaner Production. 29 (2012) 255-268. Jeswiet J, Duflou JR, Szekeres A. Trans Tech Publications.6 (2005) 449-456. Kurra S, Regalla SP. Journal of Materials Research and Technology.3(2) (2014) 158-171. Kumar A, Gulati V. Sādhanā. 43 (10) (2018) 159 (1-15). Liu Z, Li Y, Meehan PA. International Journal of Precision Engineering and Manufacturing. 14(11 )2013 1891-1899. Li Y, Liu Z, Lu H, Daniel WB, Liu S, Meehan PA. The International Journal of Advanced Manufacturing Technology. 73 (2014) 571-587. Li Y, Lu H, Daniel WJ, Meehan PA. The International Journal of Advanced Manufacturing Technology. 79 (2015) 2041-2055. Saidi B, Boulila A, Ayadi M, Nasri R. Mechanics & Industry. 16 (2015);410(1-5) Petek A, Kuzman K, Suhač B. CIRP annals. 58(1) (2009) 283-286. Pérez-Santiago R, Bagudanch I, García-Romeu ML. Key Engineering Materials. 473 (2011) 833-840.