Fe-16Mn-3.5C-3Si-3Cu高锰TWIP合金铸铁的热处理金相组织分析

Study on metallographic structure of Fe-16Mn-3. 5C-3Si-3Cu high manganese TWIP alloy cast iron via heat treatment

通过改变加热温度和保温时间,研究不同热处理工艺对Fe-16Mn-3.5C-3Si-3Cu高锰TWIP合金铸铁组织的影响,对试样进行物相分析和金相组织观察。实验结果表明:随着加热温度和保温时间的增加,组织中退火孪晶的数量增加,孪晶发育趋于完善。热处理后其室温组织为单一奥氏体;热处理的合金铸铁拉伸变形后,产生大量形变孪晶,其变形后的基体仍然保持单一奥氏体组织,未发生马氏体相变,发生了完全的TWIP效应。

Different heat treatment processes for Fe- 16Mn- 3. 5C- 3Si- 3Cu high manganese TWIP alloy cast iron were investigated through X- ray diffraction（ XRD） and metalloscope. Experimental results show that the number of annealing twins in tissue has increased,and twin development tends to be perfect with the increase of heat treatment temperature and maintaining time. The alloy cast iron was fully austenitic after heat treatment,which produced large quantities of deformation twins after alloy cast iron underwent tensile strain. The matrix after deformation kept fully austenitic structure without the occurrence of martensitic transformation,while TWIP effect occurred completely.