Effect of atmospheric humidity on the dynamic fracture strength of SiC abrasives

摘要: Abstract Silicon carbide abrasive grits were fractured dynamically in a roller crusher at ambient temperature and under controlled levels of atmospheric humidity, covering the full range from 10 to 100% relative humidity. The fracture stress depends strongly both on grit size below certain value partial pressure water vapor. effect causes an increase as diameter is decreased size. This thought be due scaling pre-existing surface defects with diameter. moisture drop any level above 0% humidity (r.h.) for sufficiently small specimens, while number fragments created crushing process increases. moisture-assisted sharpening tips defects, which serve crack initiation sites, during early stages loading. tip facilitates brittle fracture. It lowers measured enables smaller initiate secondary fractures when stored elastic energy suddenly released primary fracture; therefore, more form. results explain previously observed self-sharpening abrasives may result increased wear rates metals increase. also have implications interpretation types ceramic wear.