Q235碳素钢应变强化相变过程中铁素体晶粒取向分析

利用Ｘ射线衍射和背散射电子衍射（ＢＳＥＤ）分析了单向热压缩条件下碳素钢Ｑ２３５应变强化相变产生的铁素体及 先共析铁素体在应力作用下的晶粒取向分布特点，结果表明，通过应变强化相变产生的铁素体晶粒取向并非完全随机分布，而有较 强的（１１１）／／ ＮＤ线织构 这明显不同于形变铁素体和部分动态再结晶的铁素体晶粒取向待征，先共析铁素体的相对量与（１００） ／／ＮＤ线织构的强度对应。ＢＳＥＤ局部取向（差）定量分析表明，（１１１）取向既可来自应变强化相变，也可来自形变的先共析 铁素体。虽然先井析铁素体形变后外形为形变长条状，但内部仍存在一定的大角晶界；表明先共析铁素体在大应变下进行了一定程 度的动态再结晶

ORIENTATIONAL INSPECTION OF FERRITE GRAINS DURING STRAIN ENHANCED TRANSFORMATION IN PLAIN CARBON STEEL Q235

X-ray diffraction and BSED (back scattering electron diffraction) techniques were applied to reveal the orientation information of ferrite grains in samples from a plain low carbon steel Q235 under thermally compressed condition. Results show that the grains of dynamically transformed ferrite are not randomly orienied, but exhibit a strong (111) fiber texture as well as other weak fiber textures which were distinguished from the typical uni-axial compressed bcc textures. Dynamic recrystallization of ferrite occurs at heavy strain and weakens the deformation texture of ferrite grains. Under heavy strain the pre-eutectoid ferrite undergoes dynamic recrystallization to some extent and the intensity of (100) fiber texture is proportional to the amount of pre-eutectoid ferrite. Local orientation analysis reveals that the (111) fiber texture may either be aroused by deformed ferrite or by the strain induced ferrite nucleated in deformed austenite.