Crush strength of silicon carbide coated TRISO particles: Influence of test method and process variables

The influence of deposition temperature, methyl trichlorosilane (MTS) concentration, hydrogen carrier-gas flow rate and gas inlet design on the strength of silicon carbide coated TRISO particles was investigated using whole particle crushing strength. Crush strength was measured using soft aluminium anvils. For comparison a selection of particles were also measured with hard anvils. The influence of silicon carbide thickness was determined to allow for normalisation of all crush strength measurements to a crush strength at an equivalent thickness of 35 μm. found that the strength of the underlying pyrocarbon coated particles had a significant influence on the crush strength of the silicon carbide coated particles. Deposition temperature and gas inlet design were the only process parameters that influenced the coated particle crush strength. No evidence was found for MTS concentration and hydrogen flow rate having any influence on particle crush strength.