STUDY ON CONTINUOUS COOLING TRANSFORMATION BEHAVIOR OF COARSE GRAIN HEAT-AFFECTED ZONE IN V-N-Ti AND

来源 :第七届低合金高强度钢国际会议 | 被引量 : 0次 | 上传用户:liujiao395495759
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
  Continuous cooling transformation diagrams and microstructures of coarse grain heat-affected zone(CGHAZ)of V-N-Ti and Nb-V-Ti microalloyed steels at different cooling time form 800℃ to 500℃(t8/5)were comparatively investigated.With the increase of t8/5,the microstructure of V-N-Ti steel changes from martensite and lath bainite to ferrite,pearlite,lath bainite and granular bainite,however,lath bainite and granular bainite are the main microstructures of Nb-V-Ti steel,and hardness of the CGHAZ of both steels are decreased,but the CGHAZ of Nb-V-Ti steel has a higher hardness than that of V-N-Ti steel.Necklace-like M-A constituents along prior austenite grain boundaries are observed in CGHAZ of Nb-V-Ti steel at all of the t8/5 which could deteriorate the impact toughness.As the simulated HAZ continuous cooling transformation diagrams(SHCCT)are determined,the average transformation start temperature of V-N-Ti steel is nearly 100℃higher than Nb-V-Ti steel,the reason of which is(Ti,V)N particles did not dissolve during the welding thermal circle,and have an effect of pinning on prior austenite grain boundaries and induced the formation of ferrite at prior austenite grain boundaries.
其他文献
A new V-Ti-Mo complex micro-alloyed hot-rolled high strength sheet steel was developed by controlling a thermomechanical controlled processing(TMCP)schedule,in particular with variants in coiling temp
To develop thickness>60mm,yield strength>550MPa high-strength steel plate,the effects of heat treatment process on the microstructure and mechanical properties of plate specimens were investigated on
Potential benefits of vanadium in heat treated medium carbon bar steels are considered by reviewing examples from several recent studies.Emphasis is placed on microstructural development,strength,and
An new method is proposed to predict in sequence the phase transformation behavior and the depth of the decarburized ferrite layer with simultaneous scaling of a steel during cooling process from the
We introduce a new strengthening heat treatment of a Ni-Cr-Mo-V alloyed spring steel by partial isothermal salt-bath and subsequent air-cooling and tempering.Detailed isothermal treatments were made a
690MPa high strength steel with low yield ratio for building structure has been developed successfully by micro-alloying design and thermal-mechanical controlled processing in WISCO.The mechanical pro
In the shipbuilding industry,the welding efficiency of the ship plate not only has a great effect on the construction cost of the ship,but also affects the construction speed and determines the delive
In multi-pass welding process,various thermal cycle of both weld metal(WM)and heat affected zone(HAZ)will be subjected several times.This will make the initial microstructure occur an irreversible tra
Effect of heat-affected zone(HAZ)on spot weldability in automotive hot stamping(HS)steel sheet was investigated for automotive applications.Tensile test was performed on a tensile testing machine at a
For the purpose of obtaining the optimal microstructures and mechanical properties of the CGHAZ under high input welding,continuous cooling transformation diagrams of the coarse grain heat-affected zo