Zha Jun, Zhao Yu, Qiao Yihui, Zou Haohao, Hua Zeen, Zhu Weiwei, Han Ying, Zu Guoqing, Ran Xu
Key Laboratory of Advanced Structural Materials, Ministry of Education, Changchun University of Technology, Changchun 130012, China.
School of Materials Science and Engineering, Changchun University of Technology, Changchun 130012, China.
Materials (Basel). 2023 Feb 14;16(4):1592. doi: 10.3390/ma16041592.
In order to study the effect of the rolling process and aging on the microstructure evolution and mechanical and tribological properties of the material, room-temperature rolling (RTR), cryogenic rolling (CR), and deep cryogenic treatment after rolling (RTR + DCT) experiments were carried out on a Cu-1.0Cr-0.1Zr alloy by a large plastic deformation process. Alloy plates were aged at 550 °C for 60 min. Different rolling processes and aging treatments have different effects on the microstructure and properties of alloy plates. The alloy plate is rolled and deformed, and the grains change from equiaxed to layered. Compared with RTR and RTR + DCT treatment, CR can promote the precipitation of the Cr phase and the degree of grain fragmentation is greater. After aging treatment, the Cu-Zr mesophase compounds in the microstructure increased, the alloys treated with CR and RTR + DCT appeared to be partially recrystallized, and the number of twins in the CR alloy plate was significantly more than that of RTR + DCT. The ultimate tensile strength of the alloy plate reached 553 MPa and the hardness reached 170 HV after cryogenic rolling with 90% deformation, which indicates that CR treatment can further improve the physical properties of the alloy plate. After aging at 550 °C for 60 min, the RTR 90% + DCT alloy plate has a tensile strength of 498 MPa and an elongation of 47.9%, which is three times that of the as-rolled alloy plate. From the research on the tribological properties of alloy plates, we learned that the main wear mechanisms in the wear forms of CR and RTR + DCT alloy plates are adhesive wear and abrasive wear. Adhesive wear is dominant in the early stage, while abrasive wear is the dominant mechanism in the later stage of wear. The friction coefficient of the CR 90% alloy plate in the TD direction is close to 0.55, and the wear rate is 2.9 × 10 mm/Nm, indicating that the CR treatment further improves the wear resistance of the alloy plates.
为了研究轧制工艺和时效对材料微观结构演变以及力学和摩擦学性能的影响，通过大塑性变形工艺对Cu-1.0Cr-0.1Zr合金进行了室温轧制（RTR）、低温轧制（CR）以及轧制后深冷处理（RTR + DCT）实验。合金板材在550℃时效60分钟。不同的轧制工艺和时效处理对合金板材的微观结构和性能有不同影响。合金板材经过轧制变形后，晶粒从等轴状变为层状。与RTR和RTR + DCT处理相比，CR能促进Cr相析出，且晶粒破碎程度更大。时效处理后，微观结构中的Cu-Zr中间相化合物增多，经CR和RTR + DCT处理的合金出现部分再结晶现象，且CR合金板材中的孪晶数量明显多于RTR + DCT合金板材。在90%变形量的低温轧制后，合金板材的抗拉强度达到553MPa，硬度达到170HV，这表明CR处理能进一步改善合金板材的物理性能。在550℃时效60分钟后，RTR 90% + DCT合金板材的抗拉强度为498MPa，伸长率为47.9%，是轧制态合金板材的三倍。通过对合金板材摩擦学性能的研究发现，CR和RTR + DCT合金板材磨损形式中的主要磨损机制是粘着磨损和磨粒磨损。粘着磨损在磨损初期占主导，而磨粒磨损是磨损后期的主导机制。CR 90%合金板材在TD方向的摩擦系数接近0.55，磨损率为2.9×10⁻⁶mm³/Nm，这表明CR处理进一步提高了合金板材的耐磨性。
