TY - JOUR
T1 - Characterization of strengthening mechanism and hot deformation behavior of powder metallurgy molybdenum
AU - Xiao, Meili
AU - Li, Fuguo
AU - Xie, Hangfang
AU - Wang, Yufeng
PY - 2012/2
Y1 - 2012/2
N2 - The high-temperature deformation behavior of powder metallurgy molybdenum has been investigated based on a series of isothermal hot compression tests, which were carried out on a Gleeble-1500 thermal mechanical simulator in a wide range of temperatures (900-1450°C) and strain rates (0.01-10s-1). Through the research on the experimental stress-strain curves, it reveals that dynamic recrystallization softening effect of powder metallurgy molybdenum occurs in the temperature range from 1200°C to 1450°C, in which the flow stress is significantly sensitive to temperature. In comparison with the value of strain hardening index n which decreases along with the temperature rising, the value of strain-rate sensitivity exponent m does not change obviously; however, it increases slowly with the increasing of temperature at first and achieves a peak value at 1350°C. Furthermore, relying on the comparison of mean value of n and m, it is suggested that deformation strengthening is the main strengthening mechanism at low temperature while the rheological strengthening changes into the primary strengthening mechanism at high temperature.
AB - The high-temperature deformation behavior of powder metallurgy molybdenum has been investigated based on a series of isothermal hot compression tests, which were carried out on a Gleeble-1500 thermal mechanical simulator in a wide range of temperatures (900-1450°C) and strain rates (0.01-10s-1). Through the research on the experimental stress-strain curves, it reveals that dynamic recrystallization softening effect of powder metallurgy molybdenum occurs in the temperature range from 1200°C to 1450°C, in which the flow stress is significantly sensitive to temperature. In comparison with the value of strain hardening index n which decreases along with the temperature rising, the value of strain-rate sensitivity exponent m does not change obviously; however, it increases slowly with the increasing of temperature at first and achieves a peak value at 1350°C. Furthermore, relying on the comparison of mean value of n and m, it is suggested that deformation strengthening is the main strengthening mechanism at low temperature while the rheological strengthening changes into the primary strengthening mechanism at high temperature.
UR - http://www.scopus.com/inward/record.url?scp=80052023146&partnerID=8YFLogxK
U2 - 10.1016/j.matdes.2011.07.065
DO - 10.1016/j.matdes.2011.07.065
M3 - 文章
AN - SCOPUS:80052023146
SN - 0264-1275
VL - 34
SP - 112
EP - 119
JO - Materials and Design
JF - Materials and Design
ER -