Abstract
This paper presents laser surface modification work performed to improve the lifetime of die materials. Die material AISI H13, with typical hardness in the range of 42 to 48 HRC, offers high wear and corrosion resistance. However the cyclic high temperature conditions along with exposure to high viscosity molten metal in semi-solid forming cause the die to wear and crack with resultant shortened die lifetime. In this study, the thermal stability of die material at elevated temperature was investigated through micro-hardness testing and a metallographic study. AISI H13 samples were laser glazed using CO2 continuous wave mode laser with 10.6 µm wavelength. Samples were attached to a specially designed rotating chuck to enable it to be rotated at speeds up to 1500 rpm and allow flat surface glazing to take place. The micro- hardness was measured for as-glazed samples and annealed samples which were held at temperatures ranging from 550oC to 800oC with 50oC intervals. The metallographic study conducted examined the formation of three zones at different depths which were the glazed zone, the heat affected zone and the substrate. As a result of rapid heating and cooling from the laser glazing process, a metallic glass layer was developed which exhibited an average micro-hardness of 900 HV when exposed to 3.34E+10 W/m2 laser irradiance within a range of 0.0011 to 0.0018 s exposure time. Crystallization in glazed zone increased as the annealing temperature increased. As the annealing temperature reached above approximately 600oC, the micro-hardness decreased to approximately 600 HV (equivalent to approx. 54 HRC) due to local crystallization. These findings show potential direct application of glazed dies for non-ferrous semi-solid forming and the requirement for thermal barrier protection for application at higher temperatures.
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References
Jiang W, Molian P (2001) Nanocrystalline TiC powder alloying and glazing of H13 steel using a CO2 laser for improved life of die-casting dies. Surf Coat Technol 135:139–149
Yan H, Hua J, Shivpuri R (2007) Flow stress of AISI H13 die steel in hard machining. Mater Des 28:272–277
Li W, Qu N (2007) Study of high temperature wear resistance of hot work steel for magnesium alloy die casting. Adv Mat Res 26–28:33–36
DiMelfi RJ, Sanders PG, Hunter B, Eastman JA, Sawley KJ, Leong KH, Kramer JM (1998) Mitigation of subsurface crack propagation in railroad rails by laser surface modification. Surf Coat Technol 106:30–43
Yang Y, Song Y, Wu W, Wang M (1998) Multi-pass overlapping laser glazing of FeCrPC and CoNiSiB alloys. Thin Solid Films 323:199–202
Brabazon D, Naher S, Biggs P (2008) Laser surface modification of tool steel for semi-solid steel forming. Solid State Phenom 141–143:255–260
D. Brabazon, S. Naher, and P. Biggs.Glazing of tool dies for semi-solid steel forming. Int. J. Mater. Form. DOI 10.1007/s12289-008-0, Springer/ESAFORM 2008.
D.W. Hetzner, Laser glazed bearings. In 5th International Symposium on Bearing Steels, J. C. Hoo, W. B. Green, editors. pages 471-498, 1998, ASTM.
Glassy Metals I (1981) Ionic structure, electronic transport and crystallisation. In: Guntherodt H-J, Beck H (eds) Topics in Applied Physics. Springer Berlin, Germany
Nieh TG, Wadsworth J (2005) Homogeneous deformation of bulk metallic glasses. Scripta Materialia 54:387–392
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Aqida, .N., Maurel, M., Brabazon, D. et al. Thermal stability of laser treated die material for semi-solid metal forming. Int J Mater Form 2 (Suppl 1), 761 (2009). https://doi.org/10.1007/s12289-009-0540-7
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DOI: https://doi.org/10.1007/s12289-009-0540-7