Investigation on hot deformation behavior of AISI T1 high-speed steel

The hot deformation behavior of AISI T1 (18W-4Cr-1V) high-speed steel has b een investigated in the temperature range 950-1150 degreesC at strain rates of 0.001- 10 s(-1) and true strains of 0-0.6. The results show that the ac tivation energy for deformation, Q, decreases with the increase of strain b elow 1000 degreesC, and it changes slightly with the strain above 1000 degr eesC. Metallography shows that there are fine carbide particles precipitate d in the grains, and that these lead to dispersion hardening and an increas e in the value of Q. There are fewer of these particles above 1000 degreesC than below it. The Zener-Hollomon parameter and the hyperbolic sine functi on are used to predict the flow stress as influenced by temperature and str ain rate for different strain levels. (C) 2000 Elsevier Science Inc. All ri ghts reserved.