In order to analyze the microstructure of salt anti-freezing asphalt concrete, i e, MFL（Mafilon） modified asphalt concrete, MIP（mercury intrusion porosity） method was used to obtain the data including porosity and...In order to analyze the microstructure of salt anti-freezing asphalt concrete, i e, MFL（Mafilon） modified asphalt concrete, MIP（mercury intrusion porosity） method was used to obtain the data including porosity and pore size distribution in micro scale. Results show that the porosity grows up with the increase of immersion duration and the salt content. During the immersion, the amount of large pores（60-200 μm） grow up gradually and porosity also grows up correspondingly. Even with different immersion duration, most pores＇ size distribute is beyond 7000 nm.展开更多
Five forging experiments were designed and conducted to investigate the effect of process parameters on microstructure evolution during hot deformation for X12CrMoWVNbN10-1-1 steel.The experimental results indicated t...Five forging experiments were designed and conducted to investigate the effect of process parameters on microstructure evolution during hot deformation for X12CrMoWVNbN10-1-1 steel.The experimental results indicated that average grain size became finer with the increasing number of upsetting and stretching.Especially,the size of stretching three times with upsetting twice had the most remarkable effect on refinement,and the size was only 27.36%of the original one.Moreover,the stress model was integrated into the software and finite element models were established.Simulation results demonstrated that the strain at center point of workpiece was far larger than critical strain value in each process,so that dynamic recrystallization(DRX) occurred in each workpiece,which implied DRX could occur for several times with the increasing number of upsetting and stretching,and uniform finer microstructure would be obtained.However,the results also showed that higher temperature was an unfavorable factor for grain refinement,so the times of heating should be limited for workpiece,and as many forging processes as possible should be finished in once heating.展开更多
基金Funded by the National Natural Science Foundation of China(No.51578290)
文摘In order to analyze the microstructure of salt anti-freezing asphalt concrete, i e, MFL（Mafilon） modified asphalt concrete, MIP（mercury intrusion porosity） method was used to obtain the data including porosity and pore size distribution in micro scale. Results show that the porosity grows up with the increase of immersion duration and the salt content. During the immersion, the amount of large pores（60-200 μm） grow up gradually and porosity also grows up correspondingly. Even with different immersion duration, most pores＇ size distribute is beyond 7000 nm.
基金the National Science and Technology Major Project of China(No.2012ZX04012-011-02)the National Basic Research Program(973)of China(No.2011CB012903)
文摘Five forging experiments were designed and conducted to investigate the effect of process parameters on microstructure evolution during hot deformation for X12CrMoWVNbN10-1-1 steel.The experimental results indicated that average grain size became finer with the increasing number of upsetting and stretching.Especially,the size of stretching three times with upsetting twice had the most remarkable effect on refinement,and the size was only 27.36%of the original one.Moreover,the stress model was integrated into the software and finite element models were established.Simulation results demonstrated that the strain at center point of workpiece was far larger than critical strain value in each process,so that dynamic recrystallization(DRX) occurred in each workpiece,which implied DRX could occur for several times with the increasing number of upsetting and stretching,and uniform finer microstructure would be obtained.However,the results also showed that higher temperature was an unfavorable factor for grain refinement,so the times of heating should be limited for workpiece,and as many forging processes as possible should be finished in once heating.
