Tensile mechanical properties and fracture behavior of tungsten heavy alloys at 25-1100 °C

The tensile mechanical properties and fracture behavior of three tungsten heavy alloys (fine-grained 93W-4.9Ni-2.1Fe-0.03Y; coarse-grained 93W-4.9Ni-2.1Fe; coarse-grained 95W-3.5Fe-1.5Ni, wt%) have been investigated in the temperature range from 25 to 1100 degrees C. The results show that ultimate tensile strength, yield strength, fracture strength and nominal total elongation of the three tungsten heavy alloys are strongly temperature-dependent and in most cases decrease with increasing temperature. Fractographic observations using scanning electron microscopy (SEM) show that the fracture modes of the three alloys evolve from a mixture of W cleavage and matrix phase ductile rupture at low temperatures to a mixture of tungsten/matrix and tungsten/tungsten interfacial debonding failure at elevated temperatures. (C) 2015 Elsevier B.V. All rights reserved.