Page 167 - 《摩擦学学报》2021年第5期
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756                                     摩   擦   学   学   报                                 第 41 卷


               (a)                 1 050 MPa  (b)                  1 150 MPa  (c)                  1 250 MPa









                                      5 μm                             5 μm                           5 μm
                Iron bcc (old)  Iron fcc     Iron bcc (old)  Iron fcc         Iron bcc (old)  Iron fcc

                                                                                 5
              Fig. 10  Phase map of BF and RA phases at a distance of 10 μm from the surface during 5×10  cycles of different contact stresses
                                                          5
                                  图 10    不同接触应力运行5×10 周次距表层10 μm处BF和RA相分布图
            素达到极限水平[见图10(c)],所以磨损量与1 150 MPa                   参 考 文 献
            时相比并没有显著增加.
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            因素共同作用的结果. 试样运行高周次时[见图8(b)],                           2020, 771: 138590. doi: 10.1016/j.msea.2019.138590.
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                                                                   in fatigue crack behavior in bainitic steel[J]. International Journal of
            表面硬度相差不大,但却明显高于1 050 MPa条件下
                                                                   Fatigue, 2021, 143: 106014. doi: 10.1016/j.ijfatigue.2020.106014.
            的硬度. 这是由于在1 150 MPa条件下,表层晶粒已经                      [  3  ]  Neog  S  P,  Bakshi  S  D,  Das  S.  Microstructural  evolution  of  novel
            细化为超细等轴晶,晶粒细小,晶界增多,细晶强化作                               continuously  cooled  carbide  free  bainitic  steel  during  sliding
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                             −2
                         10
            密度为4.91×10  m ,组织在塑性变形的过程中位错                           203359.
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            高. 在接触应力为1 250 MPa时,由于晶粒细化和位错                          10.1016/j.mtcomm.2020.101531.
            强化的限度,硬化速率减慢.                                      [  5  ]  Moghaddam P V, Hardell J, Vuorinen E, et al. Dry sliding wear of

                                                                   nanostructured  carbide-free  bainitic  steels?  Effect  of  oxidation-
            4    结论                                                dominated wear[J]. Wear, 2020, 454-455: 203317. doi: 10.1016/j.wear.
                                                                   2020.203317.
                            5
                a. 在运行2×10 周次时,不同接触应力下运行表面
                                                               [  6  ]  Tan Z, An B, Gao G, et al. Analysis of softening zone on the surface
            均以黏着磨损为主,对磨损量的影响并不明显. 运行
                                                                   of  20Mn2SiCrMo  Bainitic  railway  switch[J].  Engineering  Failure
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            5×10 周次时,运行表面均以疲劳磨损为主,当接触应                             Analysis, 2015, 47: 111–116. doi: 10.1016/j.engfailanal.2014.10.013.
            力增至1 150 MPa时,磨损量增幅显著,继续增加接触                       [  7  ]  Moghaddam  P  V,  Hardell  J,  Vuorinen  E,  et  al.  Effect  of  retained
            应力,磨损量增幅不大.                                            austenite  on  adhesion-dominated  wear  of  nanostructured  carbide-
                                                                   free  bainitic  steel[J].  Tribology  International,  2020,  150:  106348.
                             5
                b. 在运行5×10 周次,接触应力为1 050 MPa时,板
                                                                   doi: 10.1016/j.triboint.2020.106348.
            条BF发生明显变形;接触应力增大为1 150 MPa时,贝
                                                               [  8  ]  Li S, Zhu R, Karaman I, et al. Development of a kinetic model for
            氏体铁素体晶粒细化成平均晶粒尺寸约为0.12 μm的
                                                                   bainitic  isothermal  transformation  in  transformation-induced
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                c. 在塑性变形的过程中,BF中位错逐渐增值、累                           10.1016/j.actamat.2013.01.032.
            积形成小角度晶界,随着变形的加剧,大角度晶界数                            [  9  ]  Lucas J P, Gerberich W W. Cyclic strain hardening of polygonal and
                                                                   acicular ferrite/bainite microstructures in microalloyed steels in the
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                                                                   Fatigue, 1985, 7(1): 31–38. doi: 10.1016/0142-1123(85)90005-2.
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