Use of acoustic emission to determine static cracking resistance in cast titanium alloys

Measurements have been made on the cracking resistance of three cast titanium alloys (Ti sub 3 Al, Ti sub 3 Al sub 3 , and Ti sub 5 Al) using acoustic emission (AE). The tests were made on prismatic and plate specimens in both three-point bending and tension. AE signals were recorded throughout the loading period up to failure. The stress intensity coefficient at the start of the cracking, K sub IS , and that at failure, K sub c , have been determined. Relationships between K sub IS and K sub c and the AE signal parameters are given. K sub IS is shown to be independent of the specimen thickness.