316 HVOF溶射したWC-Co皮膜の磨耗特性に及ぼすカーバイドサイズ及コバルト含有量の影響(OS2-3 皮膜・薄膜の環境強度,OS2 薄膜・皮膜とその膜構造の特性評価)

抄録

Twelve commercially available WC-Co powders with different average carbide sizes (0.2, 2, and 6 μm) and cobalt contents (8, 12, 17 and 25 wt.%) were sprayed on carbon steel substrates using High Velocity Oxy-Fuel (HVOF) spraying. Hardness, fracture toughness and abrasive wear properties of the coatings were investigated. The hardness decreased with increasing cobalt content, while fracture toughness slightly increased. The effect of carbide size on the hardness showed no specific trend. The wear properties was studied using Suga-type wear tester and the results showed that coatings with finer carbide had a high wear rate than the coarser ones. These behaviors were discussed with the help of microstructure observations of the coatings by scanning electron microscopy, X-ray diffraction and chemical analysis.