Journal
MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS
Volume 16, Issue 5, Pages 1092-1105Publisher
UNIV FED SAO CARLOS, DEPT ENGENHARIA MATERIALS
DOI: 10.1590/S1516-14392013005000091
Keywords
dynamic recrystallization; flow stress; microstructure; grain size
Categories
Funding
- Fundamental Research Funds for the Central Universities [CDJZR11130009]
Ask authors/readers for more resources
In order to study the dynamic recrystallization (DRX) behavior of as-extruded 42CrMo high-strength steel, a series of isothermal upsetting experiments were carried out in a temperature range of 1123 similar to 1348 K and a strain rate range of 0.01 similar to 10 s(-1) on Gleeble 1500. It was found that DRX softening is more recognizable at higher temperatures and lower strain rates, and stress level increases with increasing strain rate and decreasing deformation temperature. The types of flow stress evolution were distinguished by the following three characteristics: WH followed by DRX, WH followed by DRV, and WH followed by no dynamic softening. At a fixed temperature, the average grain size refined by DRX linearly decreases with increasing strain rate in log scale. At a fixed strain rate, the average grain size remains almost constant below 1273 K, while it rapidly increases above 1273 K. At a larger strain rate, data set of grain sizes has a smaller standard deviation to the average size value, and data have tightly grouped. This indicates that as strain rate increases, the microstructure becomes more and more uniform. The relationships between the average grain size and Zener-Hollomon parameter were nonlinearly fitted by the equation D-A = 319.81202 - 13.6114 lnZ + 0.15322 (lnZ)(2). The results from this equation show that the average grain size decreases with increasing Zener-Hollomon parameter. On the plot of DA versus lnZ, the regions corresponding to DRV (lnZ 37.8) and DRX (lnZ 37.8) were clarified clearly.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available