화학공학소재연구정보센터
Materials Science Forum, Vol.389-3, 767-770, 2002
The brittle-to-ductile transition in 4H-SiC
The technique of 4-point bend test has been used to measure the brittle-to-ductile transition (BDT) temperature in pre-cracked samples of 4H-SiC at four different strain rates. As in other semiconductors, the BDT temperature T-BDT is found to be sharp to within +/-15degrees and to shift to higher temperatures with increasing rates of the applied load (or strain rate). The results appear to be consistent with a transition temperature T-c recently observed in the yield stress of the same material as measured by compression experiments. However, strain rate measurements in 4-point bend tests are not strictly equivalent to those in compression experiments, and therefore it is difficult to directly compare the measured BDT temperatures with the yield stress transitions.