Page 21 - 摩擦学学报2025年第10期

1418 摩擦学学报（中英文） 第 45 卷

relative sliding with rolled material, and other special working conditions), the work roll will inevitably suffer oxidation,
wear and tear. The oxide film may influence the tribological properties and vice versa. Accordingly, investigating the
oxidation and tribological behaviors of HSS roll materials at high temperature and elucidating the oxidation kinetics, the
wear mechanism, and the mechanism of friction reduction and anti-wear of roll materials and counterparts will be
helpful to reduce wear and increase the life of roll materials, improve the quality of rolled materials, and heighten the
production efficiency. In this paper, the high temperature oxidation (isothermal oxidation and cyclic oxidation) and
friction experiment of one kind of HSS samples were carried out at 600 ℃, and the oxidation kinetics, the microstructure
on oxidation surface and cross-section were analyzed, as well as the wear mechanism were explored. The original HSS
sample mainly contains Fe-based solid solution and carbides (VC, Cr 7 C 3 and Mo 2 C). Although the cyclic oxidation rate
was much larger than the isothermal oxidation rate, the oxidation kinetics under both conditions conform to the parabolic
law, indicating that the oxidation was controlled by the ion diffusion process. The products were mainly Fe 2 O 3 and V 2 O 5
for isothermal oxidation, while Fe 3 O 4 and CaCO 3 dominated the cyclic oxidation, no V 2 O 5 could be detected during
cyclic oxidation. Few Cr 7 C 3 and Mo 2 C carbides were oxidized due to the better oxidation resistance. With the
proceeding of the cyclic oxidation, the CaCO 3 segregated at grain boundary firstly and then covered the surface. During
cyclic oxidation, due to the difference of thermal conductivity between matrix and carbide, the cracks initiated and
propagated at carbides. The presences of CaCO 3 and cracks facilitated the inward diffusion of oxygen, thus speeded up
the oxidation. Under cyclic oxidation, the oxide film was thicker, and the bonding strength between the oxide film and
the substrate was higher. However, due to the presence of CaCO 3 and cracks, prolonging the cycle oxidation time may
cause premature destruction of the oxide film. The friction coefficient leveled off and stabilized at about 0.47 after a
short running-in, and the wear rate of HSS pin and counterpart Q235 steel disk was low and even negative wear
−7 −7 3
[1.855×10 g/(N·m) and −1.496×10 cm /(N·m), respectively]. The wear products of HSS pin were similar with the
isothermal oxidation, with the iron oxide (Fe 3 O 4 and Fe 2 O 3 ), Fe matrix, vanadium oxide (V 2 O 5 ) and carbides can be
observed. Compared to the Fe 2 O 3 main phase after isothermal oxidation, the dominant products were Fe 3 O 4 after wear,
which was contributed to the less oxygen partial pressure during the wear test. The grooves, spalling pit, wear debris
existed on the wear surface of HSS pin, indicating the wear mechanisms of pin are mainly oxidative, abrasive and
adhesive wear. For the counterpart disc, the wear products are Fe 2 O 3 , Fe 3 O 4 , V 2 O 5 , Fe matrix and carbide, which was
same with the pin. On the wear surface of Q235 disc, the oxidation zones, wear debris zones and tribolayer containing V
and Cr could be observed. Because the Q235 is free of V, Cr, Mo, the detected V, Cr, Mo element should come from the
pin. The presence of tribolayer proves the occurrence of material transfer, and the tribolayer could separate the direct
contact of the HSS pin and Q235 disc, which was beneficial for reducing the friction coefficient and wear rate. The
material transfer was responsible for the negative wear of the counterpart disc, also may account for the reduction of
rolled material quality. The wear mechanism of the Q235 counterpart disc was oxidative and adhesive wear.
Key words: high speed steel; isothermal oxidation; cyclic oxidation; friction and wear; negative wear

随着我国制造工业的发展，对钢材的需求量和性 能佳、孔型变化小且对控制轧材负公差的轧制有利，
能要求也越来越高. 根据工信部统计，2022年我国钢 已经广泛应用于各个轧钢厂的轧机 [3-7] .
材生产总量为134 033.48万吨，其中轧材所占的比例 提高高速钢轧辊性能和服役周期，以适应轧材高
最高. 而轧辊作为钢材生产的重要部件，是不可或缺 质加工和苛刻加工工况，是轧钢行业关注的重点，其
的一部分. 按照1吨钢材需要消耗1公斤轧辊来算，轧 中，轧辊材料高温氧化及摩擦磨损行为是高速钢轧辊
辊的消耗量巨大. 因此轧辊随着轧钢技术的发展而迅 的重要研究方向之一. 由于高速钢工作辊使用过程中
猛发展 [1-2] . 轧辊材料种类繁多，常见的有低合金铸铁、 会产生高温、高应力以及与轧材间存在相对滑动等特
低合金铸钢、高铬铸铁、高镍铬铸铁、高铬钢、热工具 殊工作条件，工作辊不可避免地会发生氧化，生成氧
钢、高钨钢及高速钢等. 高速钢轧辊由于富含钨(W)、 化膜，从而影响到轧制效率、轧材质量和生产成本等.

钒(V)、铬(Cr)、钼(Mo)和钴(Co)等元素，其显微组织由 轧辊辊面氧化层在形成后，可以较大程度地减缓板坯
硬度很高的马氏体基体和极细小、弥散和硬度极高的 对轧辊的磨损，延长轧辊的使用周期，提高轧材质量，
MC、M C和M C（M为金属元素，C为碳元素）等型碳 轧辊的耗损也会降低. 如果氧化膜厚度不够，则会引
6
2
[4]
化物组成，因其高温下硬度高、耐磨性好、抗热裂性 起热粘连，从而影响产品的质量 . 而当氧化膜达到一