The rapid development in the aerospace industry requires the service performance of high-strength and heat-resistant bearing steel,especially in terms of strength and ductility synergy.A modified CSS-42L steel was obt...The rapid development in the aerospace industry requires the service performance of high-strength and heat-resistant bearing steel,especially in terms of strength and ductility synergy.A modified CSS-42L steel was obtained by multicomponent modulation,and an exceptional strength and ductility synergy of the alloy was attained through the adjusted tempering treatment.The tensile strength of 1986 MPa,the yield strength of 1622 MPa,and the uniform elongation of more than 17% were attained in the specimen tempered at 540℃,being superior to the mechanical properties of many previously reported alloys.Such superior performance originates from the generation of the high-density intermetallic compound Laves-Fe_(2)Mo,the reduction of the larger M_(6)C phase,and the formation of film-like reverse austenite.As a result,the strong interaction between the high-density dislocations of the matrix and the nanoprecipitates dominates the deformation microstructures of the specimen,strengthening the alloy.Meanwhile,the reverse austenite effectively inhibits premature crack initiation and localized stresses,increasing the uniform elongation.展开更多
Plunge grinding experiments were carried out on CSS-42L stainless steel with the white fused alumina wheel.The grinding forces were measured with variations in accumulated material removal volume.Then the morphologica...Plunge grinding experiments were carried out on CSS-42L stainless steel with the white fused alumina wheel.The grinding forces were measured with variations in accumulated material removal volume.Then the morphological features of worn grinding wheel were analyzed by optical microscopy and the grinding temperatures were measured with a thermocouple.For comparison,C45 steel was ground under the same conditions.The results indicated that the grinding forces of CSS-42L were at least twice that of C45 steel.When the accumulated removal volume overcame 375mm^3,strong adhesion was found between the abrasives and workpiece CSS-42L.Nevertheless,adhesion was hardly found after 800mm^3 workpiece C45 steel was removed.In order to enhance the machining property of CSS-42L,a brazed CBN wheel was incorporated into the grinding of CSS-42L,and the grinding forces and temperatures were found significantly decreased,whose maximum decreasing amplitude was about 70%and 80%,respectively.展开更多
In this work,fow behavior and dynamic recrystallization(DRX)mechanism of a low carbon martensitic stainless bearing steel,CSS-42L,were investigated using a thermomechanical simulator under the temperature and strain r...In this work,fow behavior and dynamic recrystallization(DRX)mechanism of a low carbon martensitic stainless bearing steel,CSS-42L,were investigated using a thermomechanical simulator under the temperature and strain rate ranges of 900 to 1100℃ and 0.1 to 20 s^(−1),respectively.The Arrhenius-type constitutive equation was established based on the fow stress curves.Moreover,the peak stress decreased with the increase in deformation temperature and the decrease in strain rate.There were two DRX mechanisms during hot deformation of the current studied steel,the main one being discontinuous dynamic recrystallization mechanism,acting through grain boundary bulging and migration,and the auxiliary one being continuous dynamic recrystallization mechanism,working through the rotation of sub-grains.On the basis of microstructural characterizations,power dissipation maps and fow instability maps,the optimized hot deformation parameters for CSS-42L bearing steel were determined as 1050℃/0.1 s^(−1) and 1100℃/1 s^(−1).展开更多
To improve the tribological performance of CSS-42L bearing steel,smooth surfaces(SSs),groovetextured surfaces(GSs),GSs with Sn-Ag-Cu(GSs-SAC),and GSs with Sn-Ag-Cu-Ti_(3)C_(2)(GSs-SACT)were prepared on CSS-42L.In addi...To improve the tribological performance of CSS-42L bearing steel,smooth surfaces(SSs),groovetextured surfaces(GSs),GSs with Sn-Ag-Cu(GSs-SAC),and GSs with Sn-Ag-Cu-Ti_(3)C_(2)(GSs-SACT)were prepared on CSS-42L.In addition,experimental studies were conducted on tribological properties.The obtained results indicated that GSs-SACT exhibited the best anti-friction and noise reduction performances.These remarkable tribological performances were attributed to the synergistic effects of grooves,Sn-Ag-Cu,and MXene-Ti_(3)C_(2).The inconsistent rules of frictional forces were improved by the grooves and SACT,which inhibit the friction-induced noise.The micro-nano size-effects of MXene-Ti_(3)C_(2) enhanced the repairing effect and anti-friction property of composite lubricants,which improved the profile characteristics of GSs-SACT.展开更多
基金financial support from the funding of National Science and Technology Major Project,China(No.J2019-VI-0019-0134).
文摘The rapid development in the aerospace industry requires the service performance of high-strength and heat-resistant bearing steel,especially in terms of strength and ductility synergy.A modified CSS-42L steel was obtained by multicomponent modulation,and an exceptional strength and ductility synergy of the alloy was attained through the adjusted tempering treatment.The tensile strength of 1986 MPa,the yield strength of 1622 MPa,and the uniform elongation of more than 17% were attained in the specimen tempered at 540℃,being superior to the mechanical properties of many previously reported alloys.Such superior performance originates from the generation of the high-density intermetallic compound Laves-Fe_(2)Mo,the reduction of the larger M_(6)C phase,and the formation of film-like reverse austenite.As a result,the strong interaction between the high-density dislocations of the matrix and the nanoprecipitates dominates the deformation microstructures of the specimen,strengthening the alloy.Meanwhile,the reverse austenite effectively inhibits premature crack initiation and localized stresses,increasing the uniform elongation.
基金supported in part by the National Natural Science Foundation of China(Nos.51305200,51235004)the Natural Science Foundation of Jiangsu Province(No.BK20130805)
文摘Plunge grinding experiments were carried out on CSS-42L stainless steel with the white fused alumina wheel.The grinding forces were measured with variations in accumulated material removal volume.Then the morphological features of worn grinding wheel were analyzed by optical microscopy and the grinding temperatures were measured with a thermocouple.For comparison,C45 steel was ground under the same conditions.The results indicated that the grinding forces of CSS-42L were at least twice that of C45 steel.When the accumulated removal volume overcame 375mm^3,strong adhesion was found between the abrasives and workpiece CSS-42L.Nevertheless,adhesion was hardly found after 800mm^3 workpiece C45 steel was removed.In order to enhance the machining property of CSS-42L,a brazed CBN wheel was incorporated into the grinding of CSS-42L,and the grinding forces and temperatures were found significantly decreased,whose maximum decreasing amplitude was about 70%and 80%,respectively.
基金fnancially supported by the Scientifc Research Project of the Department of Education in Hunan Prov ince,China(Grant No.23B0533).
文摘In this work,fow behavior and dynamic recrystallization(DRX)mechanism of a low carbon martensitic stainless bearing steel,CSS-42L,were investigated using a thermomechanical simulator under the temperature and strain rate ranges of 900 to 1100℃ and 0.1 to 20 s^(−1),respectively.The Arrhenius-type constitutive equation was established based on the fow stress curves.Moreover,the peak stress decreased with the increase in deformation temperature and the decrease in strain rate.There were two DRX mechanisms during hot deformation of the current studied steel,the main one being discontinuous dynamic recrystallization mechanism,acting through grain boundary bulging and migration,and the auxiliary one being continuous dynamic recrystallization mechanism,working through the rotation of sub-grains.On the basis of microstructural characterizations,power dissipation maps and fow instability maps,the optimized hot deformation parameters for CSS-42L bearing steel were determined as 1050℃/0.1 s^(−1) and 1100℃/1 s^(−1).
基金This work was supported by the Guangdong Basic and Applied Basic Research Foundation.
文摘To improve the tribological performance of CSS-42L bearing steel,smooth surfaces(SSs),groovetextured surfaces(GSs),GSs with Sn-Ag-Cu(GSs-SAC),and GSs with Sn-Ag-Cu-Ti_(3)C_(2)(GSs-SACT)were prepared on CSS-42L.In addition,experimental studies were conducted on tribological properties.The obtained results indicated that GSs-SACT exhibited the best anti-friction and noise reduction performances.These remarkable tribological performances were attributed to the synergistic effects of grooves,Sn-Ag-Cu,and MXene-Ti_(3)C_(2).The inconsistent rules of frictional forces were improved by the grooves and SACT,which inhibit the friction-induced noise.The micro-nano size-effects of MXene-Ti_(3)C_(2) enhanced the repairing effect and anti-friction property of composite lubricants,which improved the profile characteristics of GSs-SACT.
