ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
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 lasermelted 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 grewup 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
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/51/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.313.139.pdf
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