奥氏体不锈钢ROF内罩的失效机理分析

利用电子显微镜和成分分析技术对奥氏体不锈钢ＲＯＦ内罩的失效机理进行了研究。认为内罩外壁出现“沟槽”的主要原因是由于在密封砂层与大气交换处氢氢和氧发生化学反应放热,加上“尖端效应”使局部温度接近ＹＵＳ７０１钢的熔点,金属强度降低不断氧化剥落造成的,并据些提出了建议和对策。     

2205双相不锈钢焊接接头裂纹失效机理分析

根据金相分析和断口扫描电镜分析，对2205双相不锈钢焊接接头裂纹进行了分析。结果显示热影响区上裂纹为应力腐蚀开裂。由于焊接的热作用导致焊缝热影响区沿铁素体晶界析出的二次奥氏体和铁素体／奥氏体比例失调，从而造成应力腐蚀开裂。     

风机轴承失效分析

通过对三台风机轴承故障的RCFA分析，查找出轴承失效的根本原因，避免事故的再次发生。     

供热管道不锈钢波纹管膨胀节失效分析

针对供热管道波纹管膨胀节在设计使用期限内发生泄漏的实际问题,以宏观、微观的方法分析研究了发生开裂泄漏的波纹管的各种特征,分析了影响波纹管腐蚀问题的加工、材料、环境因素,研究结果表明,波纹管在运行中发生点腐蚀、应力腐蚀和腐蚀疲劳。成型过程中的加工硬化和运行过程中的变形强化、材料组织中的第二相和夹杂物、介质环境中Cl^-和SO4^2-含量对波纹管失效有较大影响。     

FeCrNi奥氏体不锈钢失效评定曲线研究

静拉伸试验结果表明：FeCrNi奥氏体不锈钢塑性良好,无明显屈服平台,但应力—应变关系与Ramberg-Osgood式吻合度不高,宜采用Ainsworth法基于材料应力应变构建失效评定曲线。按SINTAP标准中Option3技术路线,应用ExpAssoc指数型函数拟合真应力—应变数据,计算获得相应失效评定曲线,与两类国际通用失效评定曲线比较分析结果可知：三类失效评定曲线有区段重叠,若塑性截止线选取小于1.39,欧洲SINTAP给出通用失效评定曲线具有包络性和保守性,可用于工程评定,偏于安全。     

电机传动端轴承失效分析

我厂某型高压电机保养更换轴承,运行十天后,现场发现电机传动端轴承异音。电机拆解后发现传动端轴承内圈一侧有大面积剥落现象并伴有不规则点蚀。通过对轴承内、外圈及保持架的表面痕迹分析,结果表明轴承故障由于轴承在安装时出现轴向位移过大且轴承有与轴倾斜现象产生所造成的。     

轴承失效分析

通过对故障套圈进行宏观及微观的检测分析,判断出故障产生原因,为制定防止类似故障产生的措施提供依据。     

不锈钢螺栓断裂失效分析

某制氧设备的不锈钢螺栓紧固件在早期运行中突然发生断裂,通过采用宏观分析、微观分析、断口分析、力学性能测试、化学成分、金相检验及能谱分析等方法对其失效原因进行了分析。结果表明,应力腐蚀造成了不锈钢螺栓断裂失效。     

某电机轴承失效分析

某电机轴承在使用后出现保持架断裂。经对轴承的故障特征、理化分析和尺寸测量后发现,轴承在工作过程中承受了较大的轴向力,使零件接触表面出现异常摩擦、磨损,产生大量的摩擦热,导致轴承加速失效。     

32216轴承断裂失效分析

在对32216轴承常规抽检试验过程中,发现一套轴承在安装到试验轴上准备试验时,轴承内圈断裂.通过失效分析找到内圈断裂原因,提出改进建议,及时通知生产单位,避免不必要的损失,提高了轴承的寿命及可靠性.     

Tribological behaviour of sintered 316L stainless steel impregnated with MoS2 plain bearing

The mechanical and tribological properties of sintered 316L stainless steel impregnated with molybdenum disulfide (MoS₂) were investigated. Tests were carried out at room temperature for two specific ranges of PV value (1.1 and 1.8 MPa m/s). The results prove that the friction coefficient and the wear are strongly influenced by the addition level of MoS₂.

In this paper, MoS₂ powder was mixed with 316L powder before being processed via compacting and sintering steps. The microstructure, hardness, tensile strength and elongation at breaking point of the sintered specimens were evaluated. The friction and wear properties of the materials were examined by a partial plain bearing wear test rig under dry conditions at room temperature and in air. Although some of mechanical properties of the composite decreased with increasing MoS₂ amount, the MoS₂ was very effective in reducing the friction and wear of the composites. Particularly, the sintered 316L–15% MoS₂ materials at 1.1 PV value showed a reduction of friction coefficient by approximately 20–25% when compared to the sintered 316L specimen without addition of MoS₂. In addition, wear of specimen with addition of MoS₂ was also reduced to some extent (5–10% weight loss reduction) at this specific PV value.     

不锈钢关节轴承球面镀银工装改进

通过对不锈钢关节轴承球面镀银工装的改进,消除了原工装产生的条纹镀层和脱皮现象,达到了局部镀银的质量要求,提高了生产效率,减少了废品损失、材料消耗和劳动强度。     

6201-2RZ深沟球轴承保持架断裂故障分析

6201-2RZ轴承装在某型电机上使用至38小时发生抱死,经对轴承故障特征的理化分析,发现轴承在工作时承受了过大的轴向力,钢球的工作轨迹偏离正常位置使钢球的接触载荷增大,形成恶性循环,使润滑脂失效,造成轴承卡死,保持架断裂。     

2Cr13不锈钢温挤压工艺探讨

2Cr13钢是一种马氏体不锈钢。退火后硬度较高。冷挤压很困难。介绍通过选择合理的温挤压工艺参数，研制高效的温挤压涂料等，成功地获得了良好的挤压件方法。     

深沟球轴承早期失效分析

通过对故障轴承的综合检测及对检测结果的分析,确定该轴承工作过程中承受了过大的轴向负荷,是造成轴承早期失效的原因。     

A304不锈钢薄板激光焊接的光谱分析

为了进一步分析不同焊接参数对A304不锈钢薄板激光焊接效果的影响,该文在不同的焊接参数和激光输出方式下,采用AvaSpec-2048型光纤光谱仪对A304不锈钢薄板激光焊接的电弧进行了光谱分析。研究结果表明,激光功率、焊接速度和激光输出方式对激发出特征谱线的元素的种类和激光等离子体中元素的含量有一定的影响。     

A gun drill mechanics model analysis based on 15-5PH solid solution stainless steel

Referencing special energy model, a new gun drill mechanics model was established and the influence of the cutting parameters on axial force and torque was based on 15-5PH solid solution stainless steel through theoretical analysis and cutting tests. On the basis of the existing model, the model coefficients were modified under various cutting conditions and the integral area of the cutting edge was enlarged. The eccentricity at the bottom of the drill groove was taken into account in the integral area of the cutting edge. In the meanwhile, the torque calculation was simplified reasonably according to the theoretical analysis. The feasibility of the model was verified by experiments and the influence of cutting parameters on the axial force and torque was analyzed. The experiment data had shown that the relative error between the calculated values and the experimental values were within the acceptable range. The axial force and torque increased with the increase in cutting speed and feed rate.     

2205双相不锈钢氢致开裂行为的试验分析与模型预测

开展了2205双相不锈钢(Duplex stainless steel,DSS)氢致开裂(Hydrogen assisted cracking,HAC)行为的研究,考察了组织形态对2205双相不锈钢中氢致裂纹萌生和扩展的影响.结果表明,横向组织中的氢致裂纹扩展的长度比纵向组织中的裂纹更明显,裂纹优先萌生的位置在铁素体相...     

Correlation of microstructure with wear behaviour of deep cryogenically treated AISI D2 steel

This study aims to reveal the underlying mechanisms responsible for the enhancement of wear resistance of AISI D2 steel by deep cryogenic treatment (DCT) through in-depth microstructural analyses, and thereby attempt to correlate microstructure with wear behaviour of DCT specimens with reference to that of conventional heat treatment (CHT) and cold treatment (CT). Microstructural characterizations of the differently treated specimens have been done by image analyses of optical and SEM photographs, XRD, and EDX analyses, whereas wear behaviour has been characterized by wear rate, wear resistance, and analyses of worn surfaces, wear debris and subsurfaces. The results indicate that DCT markedly enhances the wear resistance of the selected steel compared to CHT and CT. Formation of white layer and its subsequent delamination have been identified as the operative wear mechanisms; the extent of these phenomena and the consequent wear rate is dependent on the type of treatment that determines the microstructures. The wear behaviour can be unambiguously correlated with the modifications in the precipitation behaviour of secondary carbides and reduction in the retained austenite content of the microstructure, which are the governing mechanisms for the improved of wear resistance of tool steels by DCT.     

G20CrNi2MoA钢制轴承套圈的热处理工艺

通过制定合理的G20CrNi2MoA钢制轴承套圈热处理工艺,使轴承套圈的工作表面具有高的硬度、耐磨性、高抗疲劳性,而心部具有高的强韧性,能够承受高冲击载荷,以达到轴承的使用要求。