热处理对稠油热采井专用套管HS110H的组织和性能的影响

对稠油热采井专用套管HS110H采用不同温度的亚温淬火及回火的热处理工艺,并对热处理后的试样进行冲击试验,结合试验数据和显微组织图片,分析影响热采井套管性能的因素及显微组织的变化,为提高钢的性能和寿命提供了理论依据。     

岩石掘进机盘形滚刀刀圈材料耐磨性研究

本文研究了岩石掘进机盘形滚刀刀圈材料6Mo2Cr2SinNiV钢1050℃淬火后在不同回火温度下的显微组织、硬度和冲击韧性。结果表明，回火后的组织由回火马氏体、初生碳化物和二次碳化物组成，一次碳化物和二次碳化物分别为（V,Mo）C和Fe3C。随着回火温度的升高，碳和合金元素的偏析逐渐减少。在550℃回火后，碳和合金元素的偏析完全消除，聚集的初生碳化物变成棒状并均匀分散在基体中。该钢具有良好的回火稳定性。在本文的试验范围内，试验材料在550℃回火时获得最高硬度59.0HRC，并且随着回火温度的升高其冲击韧性缓慢下降，在1050℃淬火和550℃回火后具有良好的耐磨性，其耐磨性是Q275A钢的10.59倍。     

WCp/(Co+Cr)复合材料涂层的组织及耐磨性能

采用AC-HVAF活性燃烧高速燃气喷涂设备在Q235钢表面喷涂WCp/(Co+Cr)复合材料涂层,应用光学金相显微镜分析涂层的显微组织,应用扫描电镜分析涂层断口形貌。结果表明,WCp/(Co+Cr)复合材料涂层组织致密均匀;涂层具有良好的耐磨性,其相对耐磨性比淬火回火态中碳45钢提高40倍。     

亚温淬火在 45 钢钳口板批量生产中的应用研究

研究了亚温淬火用于４５钢零件批量生产中的问题．研究表明，经亚温淬火获得（Ｍ＋Ｆ）双相组织不仅能提高零件的强韧性，而且具有硬度均匀和减小淬火变形、开裂的特点．研究指出，只要能够控制并达到稳定的生产基础条件（如含碳量，淬火温度和冷却速度等）．亚温淬火就能满足零件批量生产的要求，并取得明显的经济效益．     

固溶处理后重新加热时硼相的析出行为

本文利用Auger，薄膜透射电镜和金相染色法研究了50BA钢固溶处理后重新加热时硼相的析出行为，并以硼相的析出速率，析出硼相形态，大小，数量和分布等方面，分析讨论了加热和冷却过程中硼析出规律的相同和不同之处，试图为硼钢回火，二次淬火及亚温淬火提供理论依据。     

建筑用耐火钢组织与性能的研究

对两种工业试制耐火钢的力学性能和微观组织进行了研究。通过回火处理,研究了回火温度对微观组织的影响,同时进行了金相分析,探讨了耐火钢的高温强化机理。试验结果表明:建筑用耐火钢的室温显微组织为多边形铁素体、少量珠光体和少量粒状贝氏体的混合组织;细小、弥散分布的M-A(Martensite-Austenite)组织是建筑用耐火钢保持良好高温性能的一个主要原因;高温下良好的组织稳定性有利于提高耐火钢的高温性能;thermo-calc热力学软件计算结果表明:Mn、Mo、Cr、V等合金元素能大量熔于渗碳体中,形成合金渗碳体,对阻止高温回火组织粗化,保持良好的高温性能有较大影响。     

Cr12钢模具的热处理工艺

Cr12钢作为冷冲压模具中的一种材料,硬度和耐磨性都较好,但是它的冲击韧性比较低,容易裂开,这就不适合生产应用。加工生产成本的高低直接与模具的使用寿命密切相关,而模具寿命的长短则受到热处理工艺的影响。而将 Cr12钢经过真空热处理后,它的残余应力会缩小,同时韧性和硬度都提高。在后续的加工过程中,也会减小其变形量,提高了力学性能。本文以 Cr12钢为例介绍冷冲压模具的淬火、回火等多种热处理工艺及其对材料性能改善、使用寿命延长等所起的作用。     

35MnBM履带链轨节用钢回火特性的数值模拟

通过对35MnBM履带链轨节用钢在不同温度经1h回火后硬度的数据处理,运用淬火钢回火理论方程对其回火硬度与回火温度和回火时间之间的定量关系进行了数值模拟和验证,为合理确定35MnBM钢短时回火工艺参数提供科学依据。     

淬火回火的工艺缺陷及防止

淬火是将钢加热到临界点以上,保温后以一定的速度冷却,是钢的主要强化手段,也是最重要的热处理工艺,目的就是提高钢的力学性能;而回火则是将淬火后的钢加热到某一温度保温后冷却,其目的是降低脆性,减少或消除内应力,防止工件变形和开裂,获得工艺所要求的力学性能。尤其是调质处     

高强度铸钢斗齿材料的研制与应用

针对挖掘机、装载机斗齿材料的服务条件和性能要求,研制了一种高强度铸钢斗齿材料.研究了不同的热处理工艺对高强度铸钢斗齿材料组织和力学性能的影响,和进口斗齿进行比较,研究了高强度铸钢斗齿的磨料磨损性能.结果表明,淬火低温回火处理,高强度铸钢斗齿材料的组织为马氏体、贝氏体和奥氏体复相组织,力学性能为强度(σb)≥1 650 MPa,冲击韧度(AKU)≥20 J,硬度46～52 HRC,耐磨性能达到进口斗齿的耐磨性能,淬火低温回火齿座材料的力学性能为强度(σb)≥1 080 MPa,冲击韧度(AKU)≥40 J,硬度320～380 HB.淬火低温回火高强度铸钢斗齿材料具有良好的强韧性,并介绍了高强度铸钢斗齿材料的应用结果.     

桥梁用钢拉杆性能研究

随着大直径钢拉杆在桥梁的应用越来越广泛,对了解40Cr材料应用于钢拉杆的机械性能,确保桥梁的运营安全是十分有必要的,并为后期拉杆的设计提供技术参考。本文研究了从同一根大直径棒材中取样试验,分别进行了无热处理、正火热处理、调质热处理及正火+调质热处理等状态的取样试验对比,同时还从调质后的不同硬度及是否采用锻造工艺,分别进行了机械性能对比,对40Cr材料性能有了进一步的了解,最后通过金相组织比较得出冲击性能不合格的原因,对深入了解40Cr材料性能提供了帮助。     

大型挖掘机零件热处理技术要求规律性的探讨

根据引进美国P&H公司挖掘机制造技术,探讨了大型挖掘机零件热处理技术要求的规律性。给出了常用的调质硬度范围,普碳素钢4档,合金钢8档;按模数大小规定了不同钢种的表面淬火硬度以及关于渗碳层深度和相啮合齿轮的硬度匹配。     

Dual-phase steel rebars for high-ductile r.c. structures, Part 1: Microstructural and mechanical characterization of steel rebars

The considerable influence of steel’s mechanical behaviour on the dissipative capacity of r.c. structures has led to increasing interest in optimizing the mechanical properties of the reinforcing bars used for seismic applications.

The work presented herein is part of a broad-ranging study on the potential utilization of highly innovative types of steel for reinforced concrete earthquake-resistant structures. In particular, we present the main results obtained in experimental trials on a low-C, Mn–Si steel in the form of concrete reinforcing bars subjected to intercritical tempering treatment in a temperature range between 740 and 820 C to obtain various dual-phase ferrite–martensite structures. The samples were characterized via mechanical tests and metallographic analyses in order to correlate the bars’ characteristics with the microstructure of the steel itself.

Experimental characterization of this steel has allowed for the development of a mathematical model to enable the evaluation of the ductility performance of concrete structural elements reinforced with dual-phase steel bars.     

Comparison of Charpy absorbed energy of heat affected zones in low and high toughness steel

In this study, the relationship between the heat cycle and the Charpy absorbed energy is defined by simulating various heat cycles by performing the synthetic HAZ test using steel with a relatively high Charpy absorbed energy and steel with a distinctly low Charpy absorbed energy. On the basis of this relationship, the authors have studied the effects of the steel toughness on the Charpy absorbed energy of weld HAZs inputted the several type of welding heat cycle. As the results, the Charpy absorbed energy of the CGHAZ dropped in the case of single-pass welding, but the Charpy absorbed energy increased considerably when the maximum temperature decreased, irrespective of the steel toughness. The Charpy absorbed energy of the weld interface in multi-layer welding was greatly susceptible to the achieved temperature after the maximum achieved temperature, and the range of the temperature after the maximum temperature was achieved in which the Charpy absorbed energy was recovered was found to be different depending on the steel toughness.     

低温环境中Q345qD对接焊缝力学性能与冲击韧性

焊接钢桥在低温环境的断裂评估对焊接节点的力学性能及冲击韧性随温度变化规律研究提出了迫切的需求。本文对Q345qD对接焊缝进行了硬度测试、低温拉伸试验和低温冲击试验,得到焊接接头的硬度分布规律和5个温度点下强度、塑性、断裂及冲击韧性等参数,提出屈服应力、极限应力和冲击功随温度变化的关系曲线。结果表明,随环境温度的降低,Q345qD对接焊缝的屈服应力和极限应力有所增加,屈强比减小,冲击韧性下降,塑性指标和断裂应力没有明显变化。与高强度钢材对接焊缝相比,Q345qD对接焊缝冲击功中弹性功占比较小,对温度的敏感性更高。     

Investigation of thermal effects on mechanical properties of 9Cr-1Mo to 9Cr-1Mo welded joints for high-temperature applications

Modified 9CR-1MO usage has been highly increased in recent years mainly under high-temperature application. This paper focusses on microstructure without post heat treatment and hardness, stress analysis of weld zone, heat affected zone and parent metal with and without post heat treatment. Here, among many suitable welding processes, we have been chosen Tungsten Inert Gas Welding with an appropriate filler rod ER308L.The post heat treatment is been carried out by an annealing process. The study of microstructure for 9cr-1mo steel mainly describes size and shape of grains by the Scanning Electronic Microscope, micro, and macro structure examination. The tensile and hardness strength of the 9cr-1mo steel has been determined by using suitable equipment throughout the base metal and weld zone. The microstructure is uniform and free from a dendritic pattern, the ductility of material more after annealing and the hardness of material become uniform overall except in HAZ.     

回火对冷轧带肋钢筋抗拉性能的影响

通过对冷轧带肋钢筋出现的延伸率低问题的分析,提出以回火处理来提高冷轧带肋钢筋的延性,强度仍满足要求。进行了不同温度的回火试验,找出了最佳的回火温度,解决冷轧带肋钢筋延性不足的问题。     

自来水厂排泥水的调质和浓缩

在整个排泥水处理工艺中,排泥水的调质和浓缩是关键。通过对现阶段自来水厂排泥水浓缩和调质的研究成果、技术方法和工程应用的总结分析,提出对于排泥水处理系统的合理设计、优化运行是非常必要的。     

Experimental study on mechanical properties and toughness of Q460C high-strength steel and its butt welded joint at low temperature

Compared with the conventional steel structure, the high-strength steel structures are at more risk of brittle fracture, especially in cold regions. In the present study, a series of tests (such as uniaxial tensile test, Charpy impact test and three-point bending test) were carried out at low temperature to investigate the mechanical properties and toughness of Q460C steel and its butt welded joint, fracture micro-mechanisms were analyzed as well. The ductility indices and the toughness indices all decrease with temperature decreases, the heat affected zone (HAZ) in welded joint is more critical to fracture than the base material. The fracture toughness of high-strength steel Q460C is relatively lower than the other three conventional steels (i.e. Q235, Q345 and Q390). In this study, rich experimental data were collected so as to provide reference for the fracture resistant design of high-strength steel structures in cold regions.