The influence of fast neutron irradiation and irradiation temperature on the tensile properties of wrought LCAC and TZM molybdenum

Irradiation hardening in unalloyed and ODS molybdenum during low dose neutron irradiation at 300°C and 600°C

“…For irradiations at 300°C the width of the denuded zones is negligible, and the tensile DBTT for ODS Mo is identical to values of about 800°C obtained from commercially available low carbon arc cast (LCAC) molybdenum and TZM [27]. A fine grain size and lower interstitial levels have also been shown to result in slightly lower DBTT values for LCAC Mo with a DBTT of 300°C observed for 600°C irradiations, as compared to 700°C for commercially available TZM [32]. Low DBTT values of room-temperature have been reported for unalloyed molybdenum that contains low interstitial levels (30 ppm carbon and 5 ppm oxygen) and has a fine grain size of 2 lm for irradiations at 373°C, 519°C, and 600°C, although brittle behavior was observed in this experiment for irradiations at 406°C [28].…”

“…Since the nucleation and growth of the loops and voids that impede dislocation flow depend on point defect transport kinetics, defect formation can be influenced by pre-existing microstructural sinks and interstitial impurities [3][4][5][6][27][28][29][30][31][32]. The fine grain size and fine oxide particle dispersion of ODS molybdenum has been shown to result in improved resistance to irradiation embrittlement for irradiations at 600°C exhibiting a DBTT of room-temperature as opposed to 700°C observed for TZM [27].…”

Dose dependence of true stress parameters in irradiated bcc, fcc, and hcp metals

“…Ductile metals experience an increase of strength and reduction of ductility after low temperature irradiation, which sometimes results in embrittlement [1][2][3][4][5][6][7][8][9]. In recent studies, the true stress-true strain behavior has been emphasized in the analysis of radiation effects to understand the correlation between microstructural evolution and mechanical properties [10][11][12][13].…”

A study of hot deformation behavior and microstructural characterization of Mo–TZM alloy

“…Molybdenum and niobium base alloys are being considered as the most promising materials [1] for such applications where conventional nickel or cobalt base superalloys cannot be used. Mo possesses high strength and creep resistance at high temperatures, high thermal conductivity, low coefficient of thermal expansion and excellent corrosion resistance against liquid metals [2][3][4][5][6][7]. Mo-TZM is a potent Mo base alloy containing 0.5-0.8%Ti, 0.08-0.1%Zr, and 0.016-0.02%C (wt%).…”

“…Mo-TZM alloy shows void swelling and irradiation embrittlement behavior at temperatures below 800°C. However, irradiation at temperatures greater than 800°C results in little change in mechanical properties due to annihilation of point defects produced by neutron irradiation [4,21]. Thermally activated vacancy diffusion mechanism operates at these high temperatures causing reduction in defects and hence embrittlement.…”