Accession Number : ADA554317


Title :   Ductile to Brittle Transition Behaviour of HSLA-65 Steel Welds: Dynamic Tear Testing


Descriptive Note : Technical memo


Corporate Author : DEFENCE RESEARCH AND DEVELOPMENT ATLANTIC DARTMOUTH (CANADA)


Personal Author(s) : Aucoin, Neil M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a554317.pdf


Report Date : Jan 2011


Pagination or Media Count : 62


Abstract : HSLA-65 steel (ASTM A945, grade 65) is regarded as an excellent naval ship steel. The use of this steel in future naval platforms, which may be required to serve in Arctic conditions, requires a detailed knowledge of the steel's low temperature mechanical properties, particularly when the steel is welded. A previous study on the transition temperature, conducted by Bayley and Mantei, showed that the transition temperature was significantly higher than the requirement of -40 deg C in the heat affected zone of flux-cored arc welding (FCAW) welds. The current study re-examines the transition behaviour of HSLA-65 welds using dynamic tear testing, where specimens are significantly larger than in Charpy tests and could more accurately predict the behaviour of large scale structures. The current study also examines an alternate approach for determining the energy absorbed during a dynamic tear test using the integral definition of work. The results of this study show that transition temperatures determined through dynamic tear testing are much higher than those determined through Charpy impact testing. Several areas of each weld were tested. In all cases, the fusion line of the weld was found to have the highest transition temperature, the heat affected zone was found to have the lowest transition temperature, and the weld metal fell somewhere in between. Based on a transition temperature requirement of less than -40 deg C, none of the welds tested was found to be fit for service in Arctic conditions.


Descriptors :   *ARC WELDS , *DUCTILE BRITTLE TRANSITION , *STEEL , CANADA , CHARPY IMPACT TESTS , DYNAMIC TESTS , LOW TEMPERATURE , NAVAL VESSELS , TRANSITION TEMPERATURE


Subject Categories : Properties of Metals and Alloys
      Couplers, Fasteners, and Joints


Distribution Statement : APPROVED FOR PUBLIC RELEASE