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本文研究了工业用50CrVA及65Si2MnWA两种弹簧钢的形变热处理。原钢丝直径为2.53毫米,采用电接触加热和拉拔的方法进行形变热处理工艺。奥氏体化温度为950℃,形变温度为650、580、520和400℃,形变量为0～40%,形变后钢丝分别用水冷、油冷和空气冷却,以兹比较,将经过一定的形变热处理后的钢丝分别在100、250、350、500及600℃同火30分钟,确定了囘火温度对形变热处理后机械性能的影响惭芯苛酥馗慈却矶云浠敌阅艿挠跋臁S氪送?也进行了金相与物理检验。研究结果表明;50CrVA钢及65Si2MnWA钢分别进行了35%及40%的低温形变热处理后,和未形变者比较,强度极限分别提高了32.2%及41.6%,屈服极限分别提高了37.8%及48.4%,硬度分别提高了Hvi02公斤/毫米~2及Hv32公斤/毫米~2。使得这两种钢在具有可满足的塑性条件(δ≥5%,ψ≥20%)下,强度极限达到了280公斤/毫米~2及314公斤/毫米~2。屈服极限达到了270公斤/毫米~2及292公斤/毫米~2。最合适的形变温度为520℃左右,形变后应水冷。低温形变热处理能大大提高钢的抗囘火稳定性缭?00℃同火时的机械性能和普通热处理比较,在相同的塑性条件下,屈服极限分别提商了80.5%(50CrVA)及62.0%(65Si2MnWA),强度极限分别提高了64.0%及59.0%。试验证明:不论在珠光体还是在过冷奥氏体状态下进行冷作硬化,其遗传性是相当巩固的。研究结果表明:这种方法不仅有快速热处理的特点,而且能此较稳定地控制形变热处理的各个工艺参数,因而获得了满意的机械性能。对于试制超高强度的钢丝具有现实意义。
This paper studies the industrial heat treatment of two types of spring steel, 50CrVA and 65Si2MnWA. The original wire diameter of 2.53 mm, the use of electrical contact heating and drawing method for deformation heat treatment process. Austenitizing temperature of 950 ℃, deformation temperature of 650,580,520 and 400 ℃, the deformation of 0 ~ 40%, after deformation of the wire were water-cooled, oil-cooled and air-cooled, in this comparison, will be a certain amount of The effect of tempering temperature on the mechanical properties after heat treatment was confirmed by heat treatment at 100, 250, 350, 500 and 600 ℃ respectively for 30 minutes. The influence of tempering temperature on the mechanical properties after heat treatment was confirmed.艿 Scratch Postscript S krypton send ? Also conducted metallographic and physical examination. The results show that the ultimate strength of the 50CrVA and 65Si2MnWA steels increased by 32.2% and 41.6%, respectively, and the yield limit increased by 37.8% and 48.4%, respectively, compared with those without deformation after low-temperature heat treatment of 35% and 40% , Hardness increased respectively Hvi02 kg / mm ~ 2 and Hv32 kg / mm ~ 2. These two steels achieve 280 kg / mm 2 and 314 kg / mm 2 strength limits with satisfiable plastic conditions (δ ≥ 5%, ψ ≥ 20%). Yield limit reached 270 kg / mm ~ 2 and 292 kg / mm ~ 2. The most suitable deformation temperature of about 520 ℃, after deformation should be water-cooled. Low-temperature deformation heat treatment can greatly improve the anti-tempering stability of steel Liao? 00 ℃ at the same mechanical properties and heat treatment compared with the same plastic conditions, the yield limit respectively 80.5% (50CrVA) and 62.0 % (65Si2MnWA), the strength limit increased by 64.0% and 59.0% respectively. Experiments show that: whether in the pearlite or undercooled austenite cold hardening, its hereditary is quite solid. The results show that this method not only has the characteristics of rapid heat treatment, but also can control the various process parameters of the deformation heat treatment more stably and obtain satisfactory mechanical properties. For the trial of ultra-high strength steel has practical significance.