The fabrication of high volume fraction (HVF) M7C3 (M=Cr, Fe) reinforced Fe-based composite coating on ASTM A36 steel plate using plasma transferred arc (PTA) welding was studied. The results showed that the vol...The fabrication of high volume fraction (HVF) M7C3 (M=Cr, Fe) reinforced Fe-based composite coating on ASTM A36 steel plate using plasma transferred arc (PTA) welding was studied. The results showed that the volume fraction of carbide M7C3 was more than sixty percent, and the relative wear resistance of the coating tested on a block-on-ring dry sliding tester at constant load (100 N) and variable loads (from 100 to 300 N) respectively was about 9 and 14 times higher than that of non-reinforced a-Fe coating. In addition, under constant load condition the friction coefficients (FCs) of two coatings increased first and then decreased with increasing sliding distance. However, under variable loads condition the FCs of non-reinforced a-Fe based coating increased gradually, while that of HVF MTC3 reinforced coating decreased as the load exceeded 220 N. The worn surface of non-reinforced a-Fe based coating was easily deformed and grooved, while that of the HVF M7C3 reinforced coating was difficult to be deformed and grooved.展开更多
The transformation induced plasticity (TRIP) steels effect occurs because of the martensitic transformation of retained austenite during plastic deformation,and it provides the steel with excellent strength and ductil...The transformation induced plasticity (TRIP) steels effect occurs because of the martensitic transformation of retained austenite during plastic deformation,and it provides the steel with excellent strength and ductility.While welding remains a vital part of auto body manufacturing,the weldability of TRIP steels is problematic,and this prevents its adoption for many applications in the automotive industry.This present work studies the effects of welding and post-weld heat treatment on the microstructure of TRIP steels.It is found that the microstructures of the fusion zone and the heat affected zone (HAZ) are changed after high-temperature heat treatment.Hardness tests revealed that fusion zone hardness decreased with increasing of temperatures in the post-weld heat treatment on the laser weld seam.The rolling performance of the welding seam and the seam of post-weld heat treatment were also studied.展开更多
基金Funded by the National Natural Science Fundation of China(No.51171116)the Ministry of Science and Technology of China(No.2009DFB50350)+1 种基金the Research Foundation of Education Bureau of Hubei Province,China(No.Q20122304)the Foundation of Hubei University of Automotive Technology,China(No.BK201205)
文摘The fabrication of high volume fraction (HVF) M7C3 (M=Cr, Fe) reinforced Fe-based composite coating on ASTM A36 steel plate using plasma transferred arc (PTA) welding was studied. The results showed that the volume fraction of carbide M7C3 was more than sixty percent, and the relative wear resistance of the coating tested on a block-on-ring dry sliding tester at constant load (100 N) and variable loads (from 100 to 300 N) respectively was about 9 and 14 times higher than that of non-reinforced a-Fe coating. In addition, under constant load condition the friction coefficients (FCs) of two coatings increased first and then decreased with increasing sliding distance. However, under variable loads condition the FCs of non-reinforced a-Fe based coating increased gradually, while that of HVF MTC3 reinforced coating decreased as the load exceeded 220 N. The worn surface of non-reinforced a-Fe based coating was easily deformed and grooved, while that of the HVF M7C3 reinforced coating was difficult to be deformed and grooved.
文摘The transformation induced plasticity (TRIP) steels effect occurs because of the martensitic transformation of retained austenite during plastic deformation,and it provides the steel with excellent strength and ductility.While welding remains a vital part of auto body manufacturing,the weldability of TRIP steels is problematic,and this prevents its adoption for many applications in the automotive industry.This present work studies the effects of welding and post-weld heat treatment on the microstructure of TRIP steels.It is found that the microstructures of the fusion zone and the heat affected zone (HAZ) are changed after high-temperature heat treatment.Hardness tests revealed that fusion zone hardness decreased with increasing of temperatures in the post-weld heat treatment on the laser weld seam.The rolling performance of the welding seam and the seam of post-weld heat treatment were also studied.