The Kinetics and Dry-Sliding Wear Properties of Boronized Gray Cast Iron

Abstract

Some properties of boride formed on gray cast iron (GCI) have been investigated. GCI was boronized by powder-pack method using Commercial LSB-II powders at 1123, 1173, and 1223 K for 2, 4, 6, and 8 h, respectively. Scanning electron microscopy showed that boride formed on the surface of boronized GCI had tooth-shaped morphology. The hardness of boride formed on surfaces of GCI ranged from 1619 to 1343 HV 0.025 , and quenched and tempered GCI ranged from 400 to 610 HV 0.025 . The boride formed in the coating layer confirmed by X-ray diffraction analysis was Fe 2 B single phase. Depending on boronizing time and temperature, the thickness of coating layers on boronized GCI ranged from 26 to 105 μ m. The activation energy was 209 kJ/mol for boronized GCI. Moreover, the possibility of predicting the iso-thickness of boride layers variation was studied. Dry-sliding wear tests showed that the wear resistance of boronized sample was greater than that of quenched and tempered sample.