In Situ Notched Tensile Fracture of TC21 Alloy with Different Microstructures
In order to investigate the notched toughness of TC21 alloy, different types of microstructures (lamellar, basketweave and equiaxed microstructure) prepared by different forging and heat treatment processes were studied. The microstructure was observed through the in situ SEM tensile technology. The cracks were found initiated along β grain boundary, lath α/β interface and equiaxed α/β interface. The crack easily propagate along the slip damage in the plastic area of the crack tip. The notched toughness of the TC21 alloy with the lamellar microstructure was found to be the highest among the three ones.
KeywordsTitanium alloy Microstructure In situ Notched toughness
The authors would like to acknowledge the support of the this work was supported by the National Natural Science Foundation (No. 51501150) and the program of Science Research Foundation and Scientific Research Foundation (No. 2014cx001) for Doctoral teacher from Xi’an University of Technology.
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