| Title |
Study on the growth Kinetics and Stength of complex Carbide Precipitates |
| Authors |
김한군(Han Goon Kim); 성장현(Jang Hyun Sung); 이상윤(Sang Yun Lee) |
| Abstract |
The growth kinetics and yield strength characteristics of complex carbides precipitated in Cr steels spheroidized after standardizing initial particle distributions were investigated by using various quantitative metallographic techniques. Most of the grain boundaries of ferrite matrix are outlined by a string of complex carbide particles which are determined to be (Fe, Cr)₃C. The average values of activation energy have shown that the coarsening of complex carbide precipitates involves the coupled chromium-iron-carbon diffusion. The number of second phase particles pinning ferrite grain boundaries increases with increasing the chromium content, which results in a more decreasing growth rate of ferrite grains. During spheroidization hardness changes with the Hall-Perch type relation Hv＝Ho＋K_Hl^(-½). Yield strength is affected by parameters concerning both precipitate particles and ferrite grain boundaries and varies with the following Hall-Perch type equation σ_y= σ_o+k_yλ_p.g^(-½). |