Trend of Nitriding on Chromium-Molybdenum Steel via Low Temperature Screen Plasma Technology
Affiliation(s)
Heat Treatment Technology R&BD Group, Korea Institute of Industrial Technology, Incheon, Korea. Toyota Technological Institute, Nagoya, Japan.
Heat Treatment Technology R&BD Group, Korea Institute of Industrial Technology, Incheon, Korea. Toyota Technological Institute, Nagoya, Japan.
ABSTRACT
Low temperature screen plasma technology, a high plasma density, through using a low energy supply, shows excellent effects on a low alloy chromium-molybdenum steel for plastic molds because it does not show a compound layer and a high surface hardness without a deterioration in matrix hardness. For interest about hardening depth, both the screen plasma nitriding and plasma nitro-carburizing processes were tested including nitrogen, hydrogen and a methane mixed gas environmental at 653 K, 713 K. The optical emission spectroscopy (OES) has been analyzed during screen plasma nitriding (SPN) and a nitro-carburizing process (SPNC) was proceeded at 713 K and the same pressure. I find it difficult to dissociate nitrogen molecules perfectly with neutral nitrogen atoms via the DC-plasma nitriding process. Therefore, the SPN and SPNC process have shown a high density of plasma species even though low temperature plasma conditions have a high peak intensity of Hβ and Hγ in the results of the analysis by OES. The hardness value was measured with the micro-Vickers hardness tester after the SPN, SPNC process and the chemical composition of nitriding layers were traced by GDOES. The screen nitriding layer via the screen plasma technology has shown excellent properties with a thickness depth of about 850 ~ 900 HV without the deterioration of matrix hardness value.
Low temperature screen plasma technology, a high plasma density, through using a low energy supply, shows excellent effects on a low alloy chromium-molybdenum steel for plastic molds because it does not show a compound layer and a high surface hardness without a deterioration in matrix hardness. For interest about hardening depth, both the screen plasma nitriding and plasma nitro-carburizing processes were tested including nitrogen, hydrogen and a methane mixed gas environmental at 653 K, 713 K. The optical emission spectroscopy (OES) has been analyzed during screen plasma nitriding (SPN) and a nitro-carburizing process (SPNC) was proceeded at 713 K and the same pressure. I find it difficult to dissociate nitrogen molecules perfectly with neutral nitrogen atoms via the DC-plasma nitriding process. Therefore, the SPN and SPNC process have shown a high density of plasma species even though low temperature plasma conditions have a high peak intensity of Hβ and Hγ in the results of the analysis by OES. The hardness value was measured with the micro-Vickers hardness tester after the SPN, SPNC process and the chemical composition of nitriding layers were traced by GDOES. The screen nitriding layer via the screen plasma technology has shown excellent properties with a thickness depth of about 850 ~ 900 HV without the deterioration of matrix hardness value.
KEYWORDS
Screen Plasma Technology, Plasma Nitro-Carburizing, Optical Emission Spectroscopy, Without Compound Layer, Chromium-Molybdenum Steel
Screen Plasma Technology, Plasma Nitro-Carburizing, Optical Emission Spectroscopy, Without Compound Layer, Chromium-Molybdenum Steel
Cite this paper
Yeo, K. , Kim, S. , Lee, J. , Kong, J. and Okumiya, M. (2014) Trend of Nitriding on Chromium-Molybdenum Steel via Low Temperature Screen Plasma Technology. Advances in Materials Physics and Chemistry, 4, 141-152. doi: 10.4236/ampc.2014.48017.
Yeo, K. , Kim, S. , Lee, J. , Kong, J. and Okumiya, M. (2014) Trend of Nitriding on Chromium-Molybdenum Steel via Low Temperature Screen Plasma Technology. Advances in Materials Physics and Chemistry, 4, 141-152. doi: 10.4236/ampc.2014.48017.
References
[1] Sun, Y. and Bell, T. (1997) A Numerical Model of Plasma Nitriding of Low Alloy Steels. Materials Science and Engineering: A, 224, 33-47.
http://dx.doi.org/10.1016/S0921-5093(96)10561-X [2] Tsujikawa, M., Yamauchib, N., Uedab, N., Soneb, T. and Hirosec, Y. (2004) Behavior of Carbon in Low Temperature Plasma Nitriding Layer of Austenitic Stainless Steel. Surface and Coatings Technology, 193, 309-313.
http://dx.doi.org/10.1016/j.surfcoat.2004.08.179 [3] Lan, H.-Y. and Wen, D.-C. (2012) Improving the Erosion-Corrosion Properties of Precipitation Hardening Mold Steel by Plasma Nitriding. Materials Transactions, 53, 1443-1448.
http://dx.doi.org/10.2320/matertrans.M2012083 [4] Hubbard, P., Dowey, S.J., Partridge, J.G., Doyle, E.D. and McCulloch, D.G. (2010) Investigation of Nitrogen Mass Transfer within an Industrial Plasma Nitriding System II: Application of a Biased Screen. Surface and Coatings Technology, 204, 1151-1157.
http://dx.doi.org/10.1016/j.surfcoat.2009.08.030 [5] Kim, S.G., Lee, J.H., Saito, N. and Takai, O. (2013) The Role of Activated Nitrogen Species on Double-Folded Screen Nitriding Process. Journal of Physics Conference Series, 417, 012-023.
http://dx.doi.org/10.1088/1742-6596/417/1/012023 [6] Czerwiec, T., Renevier, N. and Michel, H. (2000) Low Temperature Plasma-Asisted Nitriding. Surface and Coatings Technology, 131, 267-277.
http://dx.doi.org/10.1016/S0257-8972(00)00792-1 [7] Michel, H., Czerwiec, T., Gantois, M., Ablitzer, D. and Ricard, A. (1995) Progress in the Analysis of the Mechanisms of Ion Nitriding. Surface and Coatings Technology, 72, 103-111.
http://dx.doi.org/10.1016/0257-8972(94)02339-5 [8] Priest, J.M., Baldwin, M.J. and Fewell, M.P. (2001) The Action of Hydrogen in Low-Pressure r.f.-Plasma Nitriding. Surface and Coatings Technology, 145, 152-163.
http://dx.doi.org/10.1016/S0257-8972(01)01311-1 [9] Petitjean, L. and Ricard, A. (1984) Emission Spectroscopy Study of N2-H2 Glow Discharge for Metal Surface Nitriding. Journal of Physics D, 17, 919-929.
http://dx.doi.org/10.1088/0022-3727/17/5/008 [10] Gallo, S.C. and Dong, H. (2009) Study of Active Screen Plasma Processing Conditions for Carburising and Nitriding Austenitic Stainless Steel. Surface and Coatings Technology, 203, 3669-3675.
http://dx.doi.org/10.1016/j.surfcoat.2009.05.045 [11] Leyland, A., Fancey, K.S., James, A.S. and Matthews, A. (1990) Enhanced Plasma Nitriding at Low Pressures: A Comparison between DC and RF Techniques. Surface and Coatings Technology, 41, 295-304.
http://dx.doi.org/10.1016/0257-8972(90)90140-8 [12] Sharma, M.K., Saikia, B.K. and Bujarbarua, S. (2008) Optical Emission Spectroscopy of DC Pulsed Plasmas Used for Steel Nitriding. Surface and Coatings Technology, 203, 229-233.
http://dx.doi.org/10.1016/j.surfcoat.2008.08.036 [13] Belmonte, T., Jaoul, C. and Borges, J.N. (2004) Modelling Nitrogen Atom Flux in Post-Discharge Nitriding Processes. Surface and Coatings Technology, 188-189, 201-206.
http://dx.doi.org/10.1016/j.surfcoat.2004.08.024 [14] Musil, J., Vlcek, J. and Ruzicka, M. (2000) Recent Progress in Plasma Nitriding. Vacuum, 59, 940-951.
http://dx.doi.org/10.1016/S0042-207X(00)00404-8 [15] Pearse, R.W.B. and Gaydon, A.G. (1976) The Identification of Molecular Spectra. 4th Edition, Chapman and Hall, London/Wiley, New York.
[1] Sun, Y. and Bell, T. (1997) A Numerical Model of Plasma Nitriding of Low Alloy Steels. Materials Science and Engineering: A, 224, 33-47.
http://dx.doi.org/10.1016/S0921-5093(96)10561-X [2] Tsujikawa, M., Yamauchib, N., Uedab, N., Soneb, T. and Hirosec, Y. (2004) Behavior of Carbon in Low Temperature Plasma Nitriding Layer of Austenitic Stainless Steel. Surface and Coatings Technology, 193, 309-313.
http://dx.doi.org/10.1016/j.surfcoat.2004.08.179 [3] Lan, H.-Y. and Wen, D.-C. (2012) Improving the Erosion-Corrosion Properties of Precipitation Hardening Mold Steel by Plasma Nitriding. Materials Transactions, 53, 1443-1448.
http://dx.doi.org/10.2320/matertrans.M2012083 [4] Hubbard, P., Dowey, S.J., Partridge, J.G., Doyle, E.D. and McCulloch, D.G. (2010) Investigation of Nitrogen Mass Transfer within an Industrial Plasma Nitriding System II: Application of a Biased Screen. Surface and Coatings Technology, 204, 1151-1157.
http://dx.doi.org/10.1016/j.surfcoat.2009.08.030 [5] Kim, S.G., Lee, J.H., Saito, N. and Takai, O. (2013) The Role of Activated Nitrogen Species on Double-Folded Screen Nitriding Process. Journal of Physics Conference Series, 417, 012-023.
http://dx.doi.org/10.1088/1742-6596/417/1/012023 [6] Czerwiec, T., Renevier, N. and Michel, H. (2000) Low Temperature Plasma-Asisted Nitriding. Surface and Coatings Technology, 131, 267-277.
http://dx.doi.org/10.1016/S0257-8972(00)00792-1 [7] Michel, H., Czerwiec, T., Gantois, M., Ablitzer, D. and Ricard, A. (1995) Progress in the Analysis of the Mechanisms of Ion Nitriding. Surface and Coatings Technology, 72, 103-111.
http://dx.doi.org/10.1016/0257-8972(94)02339-5 [8] Priest, J.M., Baldwin, M.J. and Fewell, M.P. (2001) The Action of Hydrogen in Low-Pressure r.f.-Plasma Nitriding. Surface and Coatings Technology, 145, 152-163.
http://dx.doi.org/10.1016/S0257-8972(01)01311-1 [9] Petitjean, L. and Ricard, A. (1984) Emission Spectroscopy Study of N2-H2 Glow Discharge for Metal Surface Nitriding. Journal of Physics D, 17, 919-929.
http://dx.doi.org/10.1088/0022-3727/17/5/008 [10] Gallo, S.C. and Dong, H. (2009) Study of Active Screen Plasma Processing Conditions for Carburising and Nitriding Austenitic Stainless Steel. Surface and Coatings Technology, 203, 3669-3675.
http://dx.doi.org/10.1016/j.surfcoat.2009.05.045 [11] Leyland, A., Fancey, K.S., James, A.S. and Matthews, A. (1990) Enhanced Plasma Nitriding at Low Pressures: A Comparison between DC and RF Techniques. Surface and Coatings Technology, 41, 295-304.
http://dx.doi.org/10.1016/0257-8972(90)90140-8 [12] Sharma, M.K., Saikia, B.K. and Bujarbarua, S. (2008) Optical Emission Spectroscopy of DC Pulsed Plasmas Used for Steel Nitriding. Surface and Coatings Technology, 203, 229-233.
http://dx.doi.org/10.1016/j.surfcoat.2008.08.036 [13] Belmonte, T., Jaoul, C. and Borges, J.N. (2004) Modelling Nitrogen Atom Flux in Post-Discharge Nitriding Processes. Surface and Coatings Technology, 188-189, 201-206.
http://dx.doi.org/10.1016/j.surfcoat.2004.08.024 [14] Musil, J., Vlcek, J. and Ruzicka, M. (2000) Recent Progress in Plasma Nitriding. Vacuum, 59, 940-951.
http://dx.doi.org/10.1016/S0042-207X(00)00404-8 [15] Pearse, R.W.B. and Gaydon, A.G. (1976) The Identification of Molecular Spectra. 4th Edition, Chapman and Hall, London/Wiley, New York.