In-Situ Synthesis of Metal Matrix Composite Coating with Laser Melting-Solidifying Processes

Abstract:

In order to improve wear resistance of titanium alloy, with pre-placed B4C and NiCrBSi powders on Ti-6Al-4V substrate, a process of laser melting-solidifying metal matrix composite coating was studied. The coating was examined using XRD, SEM and EDS. A good metal matrix composite coating was obtained in a proper laser process. There is a metallurgical interface bonding between the coating and the substrate. During laser melting-solidifying process, high energy of laser melted the pre-placed powders and a part of Ti-6Al-4V substrate, which made Ti extend into a melting pool. A reaction between Ti and B4C took place in the melting pool, which in-situ synthesized TiB2 and TiC reinforcements in the coating. The composite coating mainly consists of γ-Ni matrix, TiB2, TiC and CrB reinforcements. Microstructure of the reinforcements obtained using the laser melting-solidifying is not as same as that of reinforcements obtained using general producing methods. Due to high cooling rate of the melting pool, TiC nucleated primarily and grew up in dendrite morphology from undercooled liquid. Encircling TiC, TiB2 precipitated later and grew up in hexagonal prism morphology. TiC and TiB2 formed an inlaid microstructure.

• Periodical: Key Engineering Materials (Volume 313)
• Pages: 139-144
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.313.139
• Online since: July 2006
• Authors: Lin Geng, Qing Wu Meng, Yan Bin Chen
• Keywords: B₄C, Laser Melting-Solidifying, Metal Matrix Composite Coating, NiCrBSi, Ti₆Al₄V Alloy

References

[1] Douglas E Wolfe, Jogender Singh and Jeff Senderson: Adv. Mater. Process. Vol. 8 (2000), p.41.

[2] Przyb Ylowicz J and Kusinski J: Mater. Process. Technol. Vol. 109 (2001), p.154.

[3] H.M. Wang, Y. L. Yu and S.Q. Li: Scripta Mater. Vol. 47 (2002), p.57.

[4] Y. Chen and H.M. Wang, Mate. Lett. Vol. 57 (2003), p.1233.

[5] J.A. Vreeling, V. Ocelik and J.T.M. De Hosson: Acta Mater. Vol. 50 (2002), p.4913.

[6] R.X. Liu, T.Q. Lei and L.X. Guo: Surf. Rev. Lett. Vol. 11 (2004), 291.

[7] R.L. Sun, D.Z. Yang and L.X. Guo: Surf. Coat. Technol. Vol. 135 (2001), p.307.

[8] S. Mridha and T.N. Baker: Surf. Eng. Vol. 13 (1997), p.233.

[9] H.C. Man, S. Zhang and F.T. Cheng: Scripta mater. Vol. 44 (2001), p.2801.

[10] I. Zergioti and G.N. Haidemenopoulos: Nanostruct. Mater. Vol. 8 (1997), p.55.

[11] Xiaonong Zhang, Weijie Lu and Di Zhang: Scripta Mater. Vol. 41 (1999), p.39.

[12] Z.Y. Ma, S.C. Tong and L. Geng: Scripta Mater. Vol. 42 (2000), p.367.

[13] Q.W. Meng, L. Geng and Z.Z. Zheng: Mater. Sci. Forum Vol. 475 (2005), p.905.