1958 Volume 27 Issue 11 Pages 671-676
Making some improvements on the mechanism and testing procedure of Murex rotational fillet hot crack test, we investigated the effect of rotational speed, welding condition and chemical composition of weld metals on the hot crack sensitivities of various electrodes. Contrary to the original report by Jones, our test has shown that high machine speed tends to give longer crack length, and there is a critical strain speed in the critical temperature range to start cracking. Sulphur has the most deleterious effect on resistance to hot cracking, and it may be concluded that the extended existence of liquid film stage is the cause of hot crack.