- Email: [email protected]
Finishing Surface After Regeneration with Laser Cladding
Available online at www.sciencedirect.com
ScienceDirect Procedia Engineering 192 (2017) 1012 – 1015
TRANSCOM 2017: International scientific conference on sustainable, modern and safe transport
Finishing surface after regeneration with laser cladding. Nowakowski Łukasza, Wijas Martaa* a
Kielce University of Technology, al.Tysiąclecia Państwa Polskiego 7, 25 – 314 Kielce, Poland
Abstract This article has presented the results of experimental research concerning the regeneration process of flat sheet metal made of C45 steel, which is difficult to weld. The regeneration process included filling the material defect of 20x20x0.75 mm with laser cladding with a powder form additive. Rough machining of the surface with cladding has been conducted at a vertical milling center, while the finishing work was performed with a surface grinder. The analysis of obtained results has been performed on the basis of measurements of selected parameters concerning the geometrical structure of the regenerated surface treated with machining. © 2017 2017Published The Authors. Published by Elsevier © by Elsevier Ltd. This is an openLtd. access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility ofthe scientific committee of TRANSCOM 2017: International scientific conference on Peer-review responsibility of the scientific committee of TRANSCOM 2017: International scientific conference on sustainable, sustainable,under modern and safe transport. modern and safe transport Keywords: Laser cladding; regeneration of surface; geometric structure of surface; face milling; grinding
1. Introduction The numerically controlled process of laser cladding, combined with machining with the use of CNC machines, is one of the modern methods, which are used to regenerate worn surfaces, that might be fully automated [6, 8, 10]. In the process of automated laser cladding, the additive, in form of a wire or powder, is provided to the machining spot by the machine. Metal powder is applied in layers on the base material and melted with that material without scratches and pores, forming a durable welding with the surface of the material [3, 7]. The advantage of laser cladding is the possibility of applying several identical or various layers of metal, depending on the need. After cooling down, those layers are treated with machining. The application of machining is to provide the regenerated surface with the desired dimension and form accuracy and the required geometric structure of the surface [2, 10]. Due to the internal tensions created in the cladding (deformation of the cladded material), the surface does not always comply with the desired
* Corresponding author. Tel.: +48-41-34-24-434 E-mail address:[email protected]
1877-7058 © 2017 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the scientific committee of TRANSCOM 2017: International scientific conference on sustainable, modern and safe transport
doi:10.1016/j.proeng.2017.06.174
1013
Nowakowski Łukasz and Wijas Marta / Procedia Engineering 192 (2017) 1012 – 1015
parameters after end milling [2, 3, 4]. In order to obtain even higher dimension and shape accuracy, the material must be treated with grinding. 2. Experimental research The research has been divided into several stages: x The first stage of research concerned making a pocket at the vertical milling center HERMLEB300 to make that pocket simulate the material defect with known dimensions and volume in a sample made of C45 steel. The view of the simulated material defect, as well as the dimensions and parameters describing that defect have been presented in Table 1. Table 1. The view of the simulated material defect and its dimensions and parameters Volume: 283,9 mm3 Surface area: 810,64 mm2 Loss in mass: 0,002 kg
Table 2. Views and pictures of the samples and measured profiles Max depth of indentation μm
Max height μm
Hole size mm2
Outside size mm2
264
117
4,17
0,18
25,4
22,6
0,21
0,21
2,5 – 14,8
1,2
0,01
0,01
Picture and a)
profile of cladded surface
Picture and b)
profile after the process of end milling
Picture and c)
profile after grinding
x The second stage of research included performance of the cladding process with the use of a LASERCELL 1005 manufactured by Trumph, the result of which was the filling of the material defect. The process of laser cladding
1014
Nowakowski Łukasz and Wijas Marta / Procedia Engineering 192 (2017) 1012 – 1015
was performed with the following parameters: power of the laser - 35 % Pmax; frequency - 20000 Hz, width of the laser beam for deposition - 3 mm, feed velocity: 1000 mm/min, gas flow Ar: 12 l.min-1, feeder rotations: 3 l.min-1, feeder gas flow He: 3 l.min-1 [12]. During the process of laser cladding, the powder used was PMNi metal powder of hardness of 57 HRC and granulation of 100 – 160 μ applied with a GTV powder conveyor. The number of cladded layers was 7. The results of the laser cladding process have been presented in Table 2a. x The rough machining of the cladded in the end milling process at the vertical milling center HERMLE B 300. The machining used the head R245-080Q27-12M produced by Sandvik Coromant that was facilitated with six plates of type 245-12T3M-PL4230. The samples were milled with application of a cooling and lubricating liquid, with the following milling parameters: vc = 215 m.min-1, vf = 510 mm.min-1, ap = 0.25 mm, ae=50 mm Table 2b [8, 9]. x The process of finishing has been performed with a surface grinder type SPC20b made by JOTES with 250x25x7699A60K7VE01-35 disc and cutting speed of vc = 30 m.s-1. The view of the sample after the grinding process and the measured profile of the grinded surface has been presented in Table 2c. x The measurement of 2D surface profiles, after the processes of: laser cladding, end milling, and grinding, has been performed with a contact profilometer Form Talysurf PGI 1230 manufactured by Taylor Hobson. The measurement speed was 0.5 mm.s-1. The measurement included an ending with a ruby ball with the gauge of 1 mm (measurement after cladding) and a conical ending with the countersink angle of 90° and tip radius of 2 μm (measurement after milling and grinding) [1, 2]. The analysis of the profiles of the surface has been conducted with Taly Map Platinium software. The results of the selected parameters concerning the geometrical surface have been presented in Table 3. Table 3. Measurements of roughness parameters Base material after milling
Cladding material after milling
Base material after grinding
Cladding material after grinding
Amplitude parameters, μm – profile of roughness Rp
1,85
1,88
0,33
0,92
Rv
1,61
2,78
0,33
0,78
Rz
3,46
4,66
0,66
1,70
Rc
1,28
2,19
0,23
0,56
Rt
4,30
9,52
0,80
2,84
Ra
0,48
0,65
0,08
0,21
Rq
0,67
0,89
0,12
0,28
0,20
0,42
0,20
0,032
Parameters of material proportion – profile of roughness Rdc, μm
0,73
1,25
Distribution parameter, mm – profile of roughness Rsm
0,073
0,149
3. The analysis and conclusion concerning measurements When analyzing the measurements and the chart of the 2D profile of the cladded surface, it has been observed that the edges of the cladding had a flash (with height of 117 μm) at the place where the last cladding was performed during the process. There has been also an indentation of 25.45 μm caused by the shrinkage of the cladded material [4, 5, 10]. The measurement of the surface of the cladding enabled determination of the parameter of milling depth for the milling process, which has been selected at the level of 0.25 mm. Performance of rough machining of the padding cladding with end milling allowed making that surface even. The detailed analysis of the surface of the profile obtained after the milling process showed that the material was not removed equally to the base material in the place where the surface was cladding.
Nowakowski Łukasz and Wijas Marta / Procedia Engineering 192 (2017) 1012 – 1015
1015
The height of unremoved material, measured from the middle of the profile line, for loss of 0.75 mm was 22.61 μm. An indentation of 22.6 μm was also observed that was found before the area joining the surface regenerated with laser cladding and the base material. When analyzing the selected parameters of roughness of the surface after the milling process (Table 3), one may notice a slightly lower quality of the geometrical structure of surface for the cladded surface in comparison to the base material. Such difference resulted from the formation of cracks and pores within the structure of the cladding, which have not been visible on the cladded surface (Table 2a), but they have been revealed due to machining (Table 2b) [11]. The analysis presented above has explicitly proved that in order to improve the shape of the surface, it is recommended to use finishing through the process of e.g. grinding. Grinding formed a surface with parameters of the surface geometrical structure that were 5 times smaller in comparison to the milling process. The value of Ra parameter after milling was 0.65 μm, while after grinding - 0.08 μm. The grinding also enabled the decrease of unevenness of the surface from the range of 48 μm for milling to 3.7 ÷ 16 μm after grinding. Thanks to the process of grinding, the cracks and pores formed due to cladding have been "covered". The phenomenon of "covering" through the process of grinding of the defects formed in the cladding requires further nondestructive testing applied e.g. in testing of welds. References [1] S. ADAMCZAK, P.ZMARZLY, D. JANECKI, Theoretical And Practical Investigations Of V-Block Waviness Measurement Of Cylindrical Parts Metrology and Measurements Systems vol: XXII, Number: 2, Pages: 181–192, 2015 [2] S. ADAMCZAK, J. BOCHNIA, Estimating the approximation uncertainty for digital materials subjected to stress relaxation tests, Metrology and Measurement Systems vol: 23, Number: 4, Pages: 545-553, 2016 [3] M. BARTOSZUK, W. GRZESIK, Numerical prediction of the interface temperature using updated Finite Difference Approach, Modeling of machining operations Book Series: Advanced Materials Research Volume: 223 Pages: 231-239, Published: 2011 [4] S. BŁASIAK, J. TAKOSOGLU, P. LASKI, Heat transfer and thermal deformations in non-contacting face seals, Journal of Thermal Science and Technology Vol: 9, Number: 2, Pages: 1-8, 2014 [5] W. GRZESIK, M. BARTOSZUK, P. NIESLONY, Finite difference method-based simulation of temperature fields for application to orthogonal cutting with coated tools, Machining science and technology, Volume: 9, Issue: 4, Pages: 529-546 Published: 2005 [6] KLIMPEL, Napawanie i natryskiwanie cieplne. Technologie, Warszawa 2000, WNT, s. 339 – 365 [7] KLIMPEL, Technologie laserowe. Gliwice 2012, WPŚ, s. 182 – 229 [8] L. NOWAKOWSKI, M. SKRZYNIARZ, E. MIKO, The impact of cooling methods on the maximum temperature of the processed object during side milling, International Conference Experimental Fluid Mechanics 2016 - Conference Proceedings Pages: 528-531 [9] L. NOWAKOWSKI, M. WIJAS, The Evaluation of the process of surface regeneration after laser cladding and face milling, 22nd International Conference Engineering Mechanics 2016, 9 -12. 05. 2016, Svratka, Czech Republic [10] S. SPADŁO, P. MŁYNARCZYK, W. DEPCZYŃSKI, Investigation of the Selected Properties of the Superficial Layer Alloying with the Tungsten Electrodes Proceedings of 24th International Conference on Metallurgy and Materials METAL 2015 Pages: 863-867 [11] M. WIJAS, L. NOWAKOWSKI, Frezowanie powierzchnii napawanych laserowo, Miesięcznik Naukowo – Techniczny MECHANIK, Agenda Wydawnicza SIMP, s. 724/320 – 328, DOI: 10.17814/mechanik.2015.8 – 9.441
ScienceDirect Procedia Engineering 192 (2017) 1012 – 1015
TRANSCOM 2017: International scientific conference on sustainable, modern and safe transport
Finishing surface after regeneration with laser cladding. Nowakowski Łukasza, Wijas Martaa* a
Kielce University of Technology, al.Tysiąclecia Państwa Polskiego 7, 25 – 314 Kielce, Poland
Abstract This article has presented the results of experimental research concerning the regeneration process of flat sheet metal made of C45 steel, which is difficult to weld. The regeneration process included filling the material defect of 20x20x0.75 mm with laser cladding with a powder form additive. Rough machining of the surface with cladding has been conducted at a vertical milling center, while the finishing work was performed with a surface grinder. The analysis of obtained results has been performed on the basis of measurements of selected parameters concerning the geometrical structure of the regenerated surface treated with machining. © 2017 2017Published The Authors. Published by Elsevier © by Elsevier Ltd. This is an openLtd. access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility ofthe scientific committee of TRANSCOM 2017: International scientific conference on Peer-review responsibility of the scientific committee of TRANSCOM 2017: International scientific conference on sustainable, sustainable,under modern and safe transport. modern and safe transport Keywords: Laser cladding; regeneration of surface; geometric structure of surface; face milling; grinding
1. Introduction The numerically controlled process of laser cladding, combined with machining with the use of CNC machines, is one of the modern methods, which are used to regenerate worn surfaces, that might be fully automated [6, 8, 10]. In the process of automated laser cladding, the additive, in form of a wire or powder, is provided to the machining spot by the machine. Metal powder is applied in layers on the base material and melted with that material without scratches and pores, forming a durable welding with the surface of the material [3, 7]. The advantage of laser cladding is the possibility of applying several identical or various layers of metal, depending on the need. After cooling down, those layers are treated with machining. The application of machining is to provide the regenerated surface with the desired dimension and form accuracy and the required geometric structure of the surface [2, 10]. Due to the internal tensions created in the cladding (deformation of the cladded material), the surface does not always comply with the desired
* Corresponding author. Tel.: +48-41-34-24-434 E-mail address:[email protected]
1877-7058 © 2017 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the scientific committee of TRANSCOM 2017: International scientific conference on sustainable, modern and safe transport
doi:10.1016/j.proeng.2017.06.174
1013
Nowakowski Łukasz and Wijas Marta / Procedia Engineering 192 (2017) 1012 – 1015
parameters after end milling [2, 3, 4]. In order to obtain even higher dimension and shape accuracy, the material must be treated with grinding. 2. Experimental research The research has been divided into several stages: x The first stage of research concerned making a pocket at the vertical milling center HERMLEB300 to make that pocket simulate the material defect with known dimensions and volume in a sample made of C45 steel. The view of the simulated material defect, as well as the dimensions and parameters describing that defect have been presented in Table 1. Table 1. The view of the simulated material defect and its dimensions and parameters Volume: 283,9 mm3 Surface area: 810,64 mm2 Loss in mass: 0,002 kg
Table 2. Views and pictures of the samples and measured profiles Max depth of indentation μm
Max height μm
Hole size mm2
Outside size mm2
264
117
4,17
0,18
25,4
22,6
0,21
0,21
2,5 – 14,8
1,2
0,01
0,01
Picture and a)
profile of cladded surface
Picture and b)
profile after the process of end milling
Picture and c)
profile after grinding
x The second stage of research included performance of the cladding process with the use of a LASERCELL 1005 manufactured by Trumph, the result of which was the filling of the material defect. The process of laser cladding
1014
Nowakowski Łukasz and Wijas Marta / Procedia Engineering 192 (2017) 1012 – 1015
was performed with the following parameters: power of the laser - 35 % Pmax; frequency - 20000 Hz, width of the laser beam for deposition - 3 mm, feed velocity: 1000 mm/min, gas flow Ar: 12 l.min-1, feeder rotations: 3 l.min-1, feeder gas flow He: 3 l.min-1 [12]. During the process of laser cladding, the powder used was PMNi metal powder of hardness of 57 HRC and granulation of 100 – 160 μ applied with a GTV powder conveyor. The number of cladded layers was 7. The results of the laser cladding process have been presented in Table 2a. x The rough machining of the cladded in the end milling process at the vertical milling center HERMLE B 300. The machining used the head R245-080Q27-12M produced by Sandvik Coromant that was facilitated with six plates of type 245-12T3M-PL4230. The samples were milled with application of a cooling and lubricating liquid, with the following milling parameters: vc = 215 m.min-1, vf = 510 mm.min-1, ap = 0.25 mm, ae=50 mm Table 2b [8, 9]. x The process of finishing has been performed with a surface grinder type SPC20b made by JOTES with 250x25x7699A60K7VE01-35 disc and cutting speed of vc = 30 m.s-1. The view of the sample after the grinding process and the measured profile of the grinded surface has been presented in Table 2c. x The measurement of 2D surface profiles, after the processes of: laser cladding, end milling, and grinding, has been performed with a contact profilometer Form Talysurf PGI 1230 manufactured by Taylor Hobson. The measurement speed was 0.5 mm.s-1. The measurement included an ending with a ruby ball with the gauge of 1 mm (measurement after cladding) and a conical ending with the countersink angle of 90° and tip radius of 2 μm (measurement after milling and grinding) [1, 2]. The analysis of the profiles of the surface has been conducted with Taly Map Platinium software. The results of the selected parameters concerning the geometrical surface have been presented in Table 3. Table 3. Measurements of roughness parameters Base material after milling
Cladding material after milling
Base material after grinding
Cladding material after grinding
Amplitude parameters, μm – profile of roughness Rp
1,85
1,88
0,33
0,92
Rv
1,61
2,78
0,33
0,78
Rz
3,46
4,66
0,66
1,70
Rc
1,28
2,19
0,23
0,56
Rt
4,30
9,52
0,80
2,84
Ra
0,48
0,65
0,08
0,21
Rq
0,67
0,89
0,12
0,28
0,20
0,42
0,20
0,032
Parameters of material proportion – profile of roughness Rdc, μm
0,73
1,25
Distribution parameter, mm – profile of roughness Rsm
0,073
0,149
3. The analysis and conclusion concerning measurements When analyzing the measurements and the chart of the 2D profile of the cladded surface, it has been observed that the edges of the cladding had a flash (with height of 117 μm) at the place where the last cladding was performed during the process. There has been also an indentation of 25.45 μm caused by the shrinkage of the cladded material [4, 5, 10]. The measurement of the surface of the cladding enabled determination of the parameter of milling depth for the milling process, which has been selected at the level of 0.25 mm. Performance of rough machining of the padding cladding with end milling allowed making that surface even. The detailed analysis of the surface of the profile obtained after the milling process showed that the material was not removed equally to the base material in the place where the surface was cladding.
Nowakowski Łukasz and Wijas Marta / Procedia Engineering 192 (2017) 1012 – 1015
1015
The height of unremoved material, measured from the middle of the profile line, for loss of 0.75 mm was 22.61 μm. An indentation of 22.6 μm was also observed that was found before the area joining the surface regenerated with laser cladding and the base material. When analyzing the selected parameters of roughness of the surface after the milling process (Table 3), one may notice a slightly lower quality of the geometrical structure of surface for the cladded surface in comparison to the base material. Such difference resulted from the formation of cracks and pores within the structure of the cladding, which have not been visible on the cladded surface (Table 2a), but they have been revealed due to machining (Table 2b) [11]. The analysis presented above has explicitly proved that in order to improve the shape of the surface, it is recommended to use finishing through the process of e.g. grinding. Grinding formed a surface with parameters of the surface geometrical structure that were 5 times smaller in comparison to the milling process. The value of Ra parameter after milling was 0.65 μm, while after grinding - 0.08 μm. The grinding also enabled the decrease of unevenness of the surface from the range of 48 μm for milling to 3.7 ÷ 16 μm after grinding. Thanks to the process of grinding, the cracks and pores formed due to cladding have been "covered". The phenomenon of "covering" through the process of grinding of the defects formed in the cladding requires further nondestructive testing applied e.g. in testing of welds. References [1] S. ADAMCZAK, P.ZMARZLY, D. JANECKI, Theoretical And Practical Investigations Of V-Block Waviness Measurement Of Cylindrical Parts Metrology and Measurements Systems vol: XXII, Number: 2, Pages: 181–192, 2015 [2] S. ADAMCZAK, J. BOCHNIA, Estimating the approximation uncertainty for digital materials subjected to stress relaxation tests, Metrology and Measurement Systems vol: 23, Number: 4, Pages: 545-553, 2016 [3] M. BARTOSZUK, W. GRZESIK, Numerical prediction of the interface temperature using updated Finite Difference Approach, Modeling of machining operations Book Series: Advanced Materials Research Volume: 223 Pages: 231-239, Published: 2011 [4] S. BŁASIAK, J. TAKOSOGLU, P. LASKI, Heat transfer and thermal deformations in non-contacting face seals, Journal of Thermal Science and Technology Vol: 9, Number: 2, Pages: 1-8, 2014 [5] W. GRZESIK, M. BARTOSZUK, P. NIESLONY, Finite difference method-based simulation of temperature fields for application to orthogonal cutting with coated tools, Machining science and technology, Volume: 9, Issue: 4, Pages: 529-546 Published: 2005 [6] KLIMPEL, Napawanie i natryskiwanie cieplne. Technologie, Warszawa 2000, WNT, s. 339 – 365 [7] KLIMPEL, Technologie laserowe. Gliwice 2012, WPŚ, s. 182 – 229 [8] L. NOWAKOWSKI, M. SKRZYNIARZ, E. MIKO, The impact of cooling methods on the maximum temperature of the processed object during side milling, International Conference Experimental Fluid Mechanics 2016 - Conference Proceedings Pages: 528-531 [9] L. NOWAKOWSKI, M. WIJAS, The Evaluation of the process of surface regeneration after laser cladding and face milling, 22nd International Conference Engineering Mechanics 2016, 9 -12. 05. 2016, Svratka, Czech Republic [10] S. SPADŁO, P. MŁYNARCZYK, W. DEPCZYŃSKI, Investigation of the Selected Properties of the Superficial Layer Alloying with the Tungsten Electrodes Proceedings of 24th International Conference on Metallurgy and Materials METAL 2015 Pages: 863-867 [11] M. WIJAS, L. NOWAKOWSKI, Frezowanie powierzchnii napawanych laserowo, Miesięcznik Naukowo – Techniczny MECHANIK, Agenda Wydawnicza SIMP, s. 724/320 – 328, DOI: 10.17814/mechanik.2015.8 – 9.441