30CrMo钢油管接头开裂原因分析

对已开裂的30CrMo钢制油管接头的材料及断口进行了分析及检测。结果表明,化学成分符合要求,金相分析和硬度检验表明热处理过程正常,断口分析和能谱分析排除了热处理致裂嫌疑。通过对裂纹脱碳情况综合分析以及对锻造过程剖析后,认为该裂纹系锻造过程所致,其原因与原材料表面存在缺陷或坯料形状不规则以及终锻温度过低有关。     

PMS钢在精密复杂塑料模具中的应用及热处理

简要分析了精密复杂模具热处理变形及硬度问题,介绍了PMS钢的性能及特点,该钢固溶后硬度低便于机械加工,成形后时效,模具硬度提高,减少了模具热处理变形,是精密复杂塑料模具最佳模具材料,并介绍了PMS钢的热处理工艺及应用。     

热处理工艺对GJW50热疲劳性能的影响

通过对用不同工艺热处理的钢结硬质合金GJW50进行热循环试验,研究了热处理工艺对该材料热疲劳性能的影响。结果表明,经淬火回火后的材料其硬度较退火后有较大提高;不同的淬火回火工艺影响材料的热疲劳抗力和在热循环中的硬度变化趋势;热处理工艺对裂纹在试样缺口处的形态及裂纹的传播方式无影响。     

热处理提高新型耐磨蚀材料性能的试验

本文主要进行了新型耐磨蚀材料的热处理工艺试验研究,同时,对材料在热处理后的抗拉强度、冲击韧性、硬度以及材料的腐蚀磨损性能进行了对比测试和分析。并利用金相显微镜和扫描电镜等对热处理后的材料组织进行了简单分析。材料在热处理后的磨蚀性能有了较大的提高,在现场应用中有很好的效果。     

由壬盘热处理工艺的模拟及实验研究

目的获取一种既高效又省时的由壬盘热处理工艺。方法选择的试件材料为42CrMo,试件模型为由壬盘。首先,用软件DEFORM模拟改进的热处理工艺,并用实验验证模拟结果。通过对比硬度与时间的关系,得到第二次改进的热处理工艺,并再次用DEFORM模拟第二次改进的热处理工艺。结果仿真所得的试件表面最大硬度值分别为264HB、297HB。实验所得试件的表面最大硬度分别为278HB、291HB。同一方案下,工艺1和工艺2的仿真与实验所得的最大硬度误差分别为5.0%、2.1%,其误差结果在可接受范围内。上述改进工艺所得试件的硬度比传统工艺所得试件的硬度高9.5%~36.9%左右。用软件模拟第二次改进的热处理工艺,所得试件表面的最大硬度分别为260HB、285HB。与传统工艺相比,其硬度要求已完全达到。结论通过结果分析,第一次改进的热处理工艺完全满足硬度要求,第二次改进的热处理工艺不仅满足了硬度要求,而且大量减少了加工时间,提高了生产效率。     

Evaluation of material properties of 3Cr-1Mo-0.25V steel by magnetic, electrical and elastic properties

The magnetic, electrical and elastic properties of 3Cr-1Mo-0.25 V steel were investigated using heat treatment procedures (as-quenched→tempered→PWHT). The mechanical properties were determined for the respective specimens with three types of heat histories. The mechanical properties (yield stress, hardness) and magnetic properties (permeability, coercive force, remanence) were inversely proportional to the heat treatment procedures. The permeability decreased linearly with an increase in the grain size; however, the yield stress, hardness, coercive force and remanence did not vary greatly with grain size. The electrical resistivity and ultrasonic velocity of the as-quenched material differed from those of the tempered/PWHT material. This trend was due to the defects, precipitates and carbides in the grain and at the grain boundary caused by the heat treatment procedures. However, the electrical resistivity and ultrasonic velocity did not vary greatly with grain size.     

热处理方式对G17CrMoV5-10材料铸件熔敷金属硬度及组织的影响

采用低碳低合金成分的FOXDCMV焊条对G17CrMoV5-10材料进行堆焊后,选择不同的焊后热处理方式,分析和讨论母材与熔敷金属的硬度、组织变化及对比。结果表明,焊后进行690℃消应后,母材及熔敷金属硬度满足标准要求,熔敷金属区硬度略低于母材;焊后经过950℃油淬+700℃重新调质热处理,母材硬度满足标准要求,而熔敷金属硬度则低于标准要求。     

TBM盘形滚刀刀圈新材质DQ50钢的研制

通过对 TBM刀圈新材质 DQ5 0钢的研究 ,总结出 DQ5 0钢满足硬度和耐磨性要求的最佳热处理工艺 ,讨论了对 DQ5 0钢刀圈硬度和耐磨性产生影响的各种因素 ,并采用最佳热处理工艺参数进行了产品试制 ,硬度达到了 HRC5 7以上 ,并进行了现场试验 ,经试验硬度、韧性及耐磨性达到了 WIRTH公司的水平 ,可以替代 WIRTH公司的刀圈而进行国产化的批量制造     

镍硬铸铁的硬化原则及影响因素

讨论了化学成分、热处理方法以及铸造方法对镍硬铸铁硬度的影响规律;介绍了镍硬铸铁件化学成分设计的原则、适宜的铸造方法和镍硬1型铸铁的代用材料;认为低温热处理能有效改善因成分设计不合理造成的铸件硬度较低的状况,变质处理可以提高镍硬铸铁的冲击韧度。     

Choice of heat treatment mode for increasing the hardness of Cu-9% Al-6% Ni-5% Fe alloy

Several modes of heat treatment are tested with the aim of raising the hardness of Cu-9% Al-6%Ni-5%Fe aluminum bronze used for fabricating axial piston pumps of launching systems. A high hardness ensuring resistance to abrasion wear is one of the main requirements on the material.     

Ultra-Jet Diagnosis of Heat Treated Material Microstructure

Metal Science and Heat Treatment - An ultra-jet diagnosis method for studying the effect of heat treatment regimes on material structure is suggested. Results of experimental studies of hardness,...     

铝合金天线钎料铺展程度及钎焊工艺控制研究

100件铝合金天线组合中,发现有21件发生钎料流出堆积。天线组合由5层3A21原材料板真空钎焊而成。对天线和原材料板材表面粗糙度、晶粒组织、析出相、焊缝组织、维氏硬度进行对比检测,并进行热处理对比实验,分析影响天线真空钎焊质量的多个因素,确认钎料在板材表面铺展程度不同的主要因素之一为表面粗糙度。失效件原材料存在晶粒较大、硬度较低的情况,通过严格控制板材热处理温度在再结晶温度以下以及板材晶粒尺寸,此类失效没有再次发生。     

热处理工艺对0Cr16Ni6不锈钢硬度的影响

硬度表征着材料抵抗外界变形的能力,是生产中检验材料性能的重要参数之一。采用不同热处理工艺对Ф60mm 0Cr16Ni6不锈钢棒料进行工艺试验,分析0Cr16Ni6钢的显微组织,研究不同热处理工艺对0Cr16Ni6钢硬度的影响规律,最终使0Cr16Ni6不锈钢硬度值达到了41～43HRC,满足了生产使用要求。     

18Ni无钴马氏体钢薄壁管径缩机理研究

采用显微组织观察、XRD分析和硬度测试,研究了热处理后18Ni无钴马氏体钢薄壁管径向收缩0.20%-0.38%的现象.结果表明,材料经旋压后组织呈现明显的织构形貌,晶粒被拉长,沿环向排列,相应硬度值升高.固溶处理后,晶粒细化并回复正常形貌,大部分残余应力消除;时效过程中,形成一定量的逆转变奥氏体,同时基体中析出弥散分布的沉淀强化相.分析表明,形变引起的内应力消除是薄壁管径缩的主要原因,时效过程产生逆转变奥氏体以及沉淀析出等相关的微观结构变化对径缩现象有明显的贡献.     

金相分析技术在钛合金航空模锻件生产中的应用

总结了金相分析技术在钛合金模锻件的锻造、热处理等实际生产中的应用情况,分析了β转变温度对锻造工艺温度、热处理工艺温度的影响规律、钛合金原材料低倍组织以及中间坯高倍组织对锻造工艺(变形量)的影响规律,为制定钛合金工艺技术规范奠定了一定的基础。     

热处理参数对5052铝合金板材力学性能的影响

以5052-H32铝合金冷轧板为研究对象,借助于单向拉伸试验、硬度测试对不同热处理参数条件下的力学性能进行研究,分析不同热处理工艺参数对5052铝合金力学性能参数的影响机制,结果表明:对5052-H32铝合金进行再次热处理时,可以显著地降低其变形抗力,提高塑性变形能力;在热处理过程中的加热温度起主要作用,在合理的热处理...     

VC-Cu-Cr-Zr复合材料组织与性能研究

根据时效强化和颗粒增强强化的双重强化机制,以Cu-Cr-Zr合金为基体,采用熔铸法制备了VC-Cu-Cr-Zr复合材料。较系统地研究了热处理工艺对VC-Cu-Cr-Zr复合材料组织和性能的影响。结果表明,热处理可明显提高VC-Cu-Cr-Zr复合材料的硬度和电导率,最佳热处理工艺为910℃×1 h固溶处理＋460℃×2.5 h时效     

Effect of Heat Treatment on Microstructure and Mechanical Properties of A380 Aluminum Alloy Deposited by Cold Spray

The microstructure and mechanical properties of cold-sprayed bulk A380 alloy were investigated after heat treatment at various conditions, using optical and electron microscopy and tensile and hardness tests, respectively. The results revealed that heat treatment increased the strength and ductility of the cold-sprayed A380 alloy deposits compared with as-sprayed state. Heat treatment showed two different effects on the mechanical properties of the deposits. On the one hand, it resulted in effective diffusion at interparticle boundaries that altered the particle bonding mechanism from pure mechanical interlocking to metallurgical bonding. Thus, the strength and ductility of the material were greatly enhanced. On the other hand, interparticle diffusion during high-temperature heat treatment resulted in growth of the Si phase and pores, which ultimately reduced the strength and elongation of the alloy. This observation was consistent with the hardness results, which showed a decreasing trend with increase of the heat treatment temperature.     

Fatigue and hardness effects of a thin buffer layer on the heat affected zone of a weld repaired Bisplate80

Heat-affected zones (HAZs) in extensively weld-repaired Bisplate80, or the parent metal (PM), have been studied and examined using hardness measurements in conjunction with fatigue crack growth measurements and detailed scanning electron microscopy (SEM) observations. Three different groups of specimens have been prepared, i.e. as-received PM, weld-repaired PM with a thin 4 mm BL between PM and weld metal (WM), and weld-repaired PM without BL. The extended compact tension (E-CT) specimens for fatigue measurements are prepared according to the ASTM specifications, which are also used for hardness measurements. Hardness and fatigue crack growth variations across the boundaries between WM, BL and PM have been measured together with detailed SEM observations. It has been found that the welding process without BL reduced both hardness and fatigue resistance, especially around the weld interface and within the HAZ. Incorporation of a thin soft BL between WM and PM has increased both hardness and fatigue resistance around the weld interface and within the HAZ.     

1Cr17Ni2铁素体含量的控制及其对性能的影响

航空发动机用1Cr17Ni2叶片经锻造及热处理后进行硬度检查,发现硬度偏低。通过在熔炼过程中调节Cr、Ni元素含量以及在后续热处理过程中逐步提高淬火温度,提出控制铁素体含量的具体办法,同时对不同铁素体含量的热处理后的棒料进行相关力学试验。结果表明:叶片硬度偏低与材料中存在较多δ?铁素体有关;1Cr17Ni2中δ?铁素体含量可以通过调节Cr、Ni元素含量及热处理过程中淬火温度进行控制,当原材料中铁素体形成元素含量高时,随着淬火温度的升高,特别是淬火温度高于1150 ℃,铁素体含量迅速增加;1Cr17Ni2合金钢中δ?铁素体含量过多时,其抗拉强度、冲击韧性、硬度等力学性能降低;通过合理调节原材料中Cr、Ni元素的含量,选择合适的热处理温度可以有效减少δ?铁素体含量,从而提高零件的力学性能。