Volokitina Irina, Siziakova Ekaterina, Fediuk Roman, Kolesnikov Alexandr
Department of Metallurgy and Mining, Rudny Industrial Institute, Rudny 111500, Kazakhstan.
Mineral Raw Material Processing Faculty, Saint Petersburg Mining University, 199106 St. Petersburg, Russia.
Materials (Basel). 2022 Jul 15;15(14):4930. doi: 10.3390/ma15144930.
This article describes a technology for the thermomechanical treatment of stainless-steel piston rings. This technology makes it possible to obtain rings with an optimal combination of plastic and strength properties that is essential for piston rings. The following thermomechanical treatment is suggested for piston rings manufacturing: quenching at 1050 °C, holding for 30 min and cooling in water, then straining by the HPT method for eight cycles at cryogenic temperature and annealing at a temperature up to 600 °C. The resulting microstructure consisted of fine austenite grains sized 0.3 μm and evenly distributed carbide particles. Annealing above this temperature led to the formation of ferrite in the structure; however, preserving the maximum fraction of austenitic component is very important, since the reduction of austenite in the structure will cause a deterioration of corrosion resistance. The strength properties of steel after such treatment increased by almost two times compared with the initial ones: microhardness increased from 980 MPa to 2425 MPa, relative elongation increased by 20%. The proposed technology will improve the strength and performance characteristics of piston rings, as well as increase their service life, which will lead to significant savings in the cost of repair, replacement and downtime.
本文介绍了一种用于不锈钢活塞环热机械处理的技术。该技术能够获得具有活塞环所需的塑性和强度性能最佳组合的活塞环。建议对活塞环制造采用以下热机械处理：在1050℃淬火，保温30分钟，然后在水中冷却，接着在低温下通过高压扭转（HPT）方法进行八次循环应变，并在高达600℃的温度下退火。所得微观结构由尺寸为0.3μm的细小奥氏体晶粒和均匀分布的碳化物颗粒组成。高于此温度的退火会导致组织中形成铁素体；然而，保持奥氏体成分的最大比例非常重要，因为组织中奥氏体的减少会导致耐腐蚀性下降。经过这种处理后，钢的强度性能与初始性能相比提高了近两倍：显微硬度从980MPa提高到2425MPa，相对伸长率提高了20%。所提出的技术将改善活塞环的强度和性能特性，并延长其使用寿命，这将显著节省维修、更换和停机成本。
