4Cr13、7Cr17Mo马氏体不锈钢组织和性能比较

文章采用金相显微镜、扫描电子显微镜(SEM)、洛氏硬度计及摩擦磨损试验机分析了4Cr13、7Cr17Mo马氏体不锈钢刀剪材料在980～1 110℃不同淬火温度下的组织、硬度和摩擦磨损性能。实验结果表明,4Cr13、7Cr17Mo的淬火组织均为马氏体、未溶碳化物和残留奥氏体,随着淬火温度升高,组织中碳化物含量均减少。相同淬火温度下,7Cr17Mo组织中未溶碳化物含量较多,硬度较高,具有更好的耐磨性。     

浅谈有关马氏体不锈钢的补焊

１工件损坏情况由某厂送来一组损坏叶轮，规格为１４００×４１０，底盘厚度为８，叶片厚度为６，材质底盘２Ｃｒ１３，叶片为１Ｃｒ１３，叶轮损坏较严重，底盘扭曲变形达１１０左右，叶片断裂，属于扭曲变形，底盘与叶片焊缝开焊，熔敷金属只有９０％左右在底盘上，而叶片焊区熔敷金属只有１０％左右。从损坏情况分析，只有很少一部分熔合较好，叶片是在焊缝热影响区撕裂。２叶轮损坏原因分析焊接规范不当，电流小、熔深浅、焊脚小、焊缝强度不够；在施焊中，可能使用压力装拼，增大了工件的钢性，焊后内应力增大；焊工操作时，焊…     

马氏体转变温度对奥氏体不锈钢的马氏体转变的影响

研究马氏体临界转变温度Ms、MD30与奥氏体不锈钢的马氏体转变之间的关系.结果表明：S30408与S30403的MD30的温度在室温范围,可以在室温下顺利进行马氏体转变,而S31603的MD30均低于-40℃,在室温下进行马氏体转变十分困难.     

马氏体不锈钢焊接分析

马氏体不锈钢属于铬不锈钢,虽焊接数量不多,但是容易出现接头裂纹、脆化和热影响区软化等问题,所以必须采取严格的焊接工艺措施保证焊接质量.该文详细地分析了马氏体不锈钢的特性和焊接性特点,并从焊材选择、焊接方法和热处理等方面阐述了可采取的焊接.     

形变诱发马氏体时效不锈钢的研制及其强化机制的研究

本文利用形变诱发马氏体相变和时效强化手段研制出一种形变诱发马氏体时效不锈钢00Cr12Ni5Mn8Cu2TiRE钢,经1050℃、0.5h固溶处理+80%冷变形+410℃、2.5h时效处理后,其σ_b≥2100MPa,ψ≥35%,δ≥4%;其耐腐蚀性能良好。该钢具有ε和α′二种诱发马氏体,当变形量达75%以上时基体主要为α′马氏体组织。文中分析了该类钢中强度指标与形变量(ε)、主要合金元素含量和α′马氏体体积分数(V_α′)之间的关系,并给出了相应的关系式。     

奥氏体不锈钢的马氏体相变对耐蚀性的影响

用电化学交流阻抗法（ＥＩＳ）俄歇电子能谱法（ＡＥＳ）和Ｘ－射线荧光电子能谱法（ＸＰＳ）研究形变诱发马氏体相变的３２１不锈钢在酸性氯化钠溶液中的耐蚀性,实验结果表明,形变诱发α′－马氏体（铁磁相）的存在的影响材料的耐蚀性,当马氏体含量〈６％和〉２２％时,材料的耐蚀性随马氏体含量的增加而降低;当马氏体相含量在６％～２２％范围内,材料的耐蚀性又随马氏体相增多而有所提高。     

5Cr15马氏体不锈钢表面包埋渗沉积Cr2N涂层及其耐腐蚀性

采用包埋渗法在5 Cr15马氏体不锈钢表面沉积Cr2 N涂层,利用SEM、EDS、XRD等对涂层的微观结构、物相组成进行表征,借助电化学工作站及腐蚀试验研究了涂层的耐腐蚀性能.结果表明,采用包埋渗法在1100℃保温4 h后,5Cr15马氏体不锈钢表面可生成致密的Cr2 N涂层及其下方的富Cr扩散层,表面沉积Cr2 N涂...     

高碳马氏体不锈钢8 Cr13 MoV钢铸态组织及碳化物

利用Thermo-Calc软件对8Cr13MoV马氏体不锈钢的凝固过程进行计算,利用光学显微镜、扫描电子显微镜和X射线衍射分析仪对铸态组织和碳化物形貌以及类型进行观察与分析,利用Gleeble热模拟试验机测定材料的静态连续冷却转变曲线.结果表明,8Cr13MoV在平衡凝固条件下组织为铁素体和M23 C6型碳化物,而在实际的凝固条件下,组织为铁素体、马氏体、残余奥氏体、M7 C3型和M23 C6型碳化物,由于偏析导致最终组织中碳化物以M7 C3型为主,少量M23 C6以薄片或树枝状分布在晶界上.由于较高的C和Cr含量,以0.1℃·s-1的冷却速率冷却时,奥氏体也会发生马氏体转变.     

超级13Cr马氏体不锈钢在CO_2 及H_2 S/CO_2 环境中的腐蚀行为

在模拟油田腐蚀环境中,通过高温、高压、CO2和H2S/CO2腐蚀实验及电化学测试,研究超级13Cr马氏体不锈钢的腐蚀行为.结果表明:在CO2腐蚀环境中,随着温度的升高,超级13Cr的均匀腐蚀速率呈稍微上升的趋势,点蚀轻微;在H2S、CO2共存条件下,超级13Cr的均匀腐蚀速率变化不大,点蚀严重,当Cl-的质量浓度为160g.L-1时,其最大点蚀深度可达28μm.超级13Cr的点蚀电位明显高于普通13Cr的点蚀电位,温度升高、Cl-的质量浓度增大和H2S气体的存在降低了超级13Cr的点蚀电位,而CO2对超级13Cr的点蚀电位影响不大;在N2、CO2环境中,超级13Cr的回复电位都在钝化区间,且回复电位较高,具有良好的再钝化能力.H2S气体的存在同样使超级13Cr的回复电位和点蚀电位显著降低.     

对马氏体不锈钢车削工艺的改进

由于马氏体不锈钢在大气、水蒸气和不超过30℃的盐水溶液、硝酸、食品介质及浓度不高的有机酸中具有足够的耐蚀性,一般被广泛用于制作抗弱腐蚀性介质并能承受冲击负荷的零件,如球阀等。 马氏不锈钢,它的强度高、塑性好,硬度高、导热性差,在加工过程中易变形。而且切削时加工硬化严重,切削抗力大,切削温度高,易导致刀具磨损严重,增加了停车时间和装刀时间,降低了生产效率;同时,由于塑性好,在加工过程     

Effect of electroslag remelting on carbides in 8Cr13MoV martensitic stainless steel

The effect of electroslag remelting (ESR) on carbides in 8Cr13MoV martensitic stainless steel was experimentally studied. Phases precipitated from liquid steel during solidification were calculated using the Thermo-Calc software. The carbon segregation was analyzed by original position analysis (OPA), and the carbides were analyzed by optical microscopy (OM), scanning electron microscopy (SEM), energy- dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results indicated that more uniform carbon distribution and less segregation were obtained in the case of samples subjected to the ESR process. After ESR, the amount of netty carbides decreased significantly, and the chromium and vanadium contents in the grain-boundary carbides was reduced. The total area and average size of carbides were obviously smaller after the ESR process. In the sample subjected to ESR, the morphology of carbides changed from lamellar and angular to globular or lump, whereas the types of carbides did not change; both M₂₃C₆ and M₇C₃ were present before and after the ESR process.     

无镍不锈钢17Cr10Mn2MoN的制备与性能

采用气雾化法制备含氮无镍不锈钢粉末，利用热等静压成形并对材料进行固溶处理．热等静压后，材料具有良好的强度、塑性及韧性，抗拉强度为850MPa，屈服强度为505MPa，延伸率为44．5％，断面收缩率为47．5％，冲击功为44J．材料经1100℃固溶处理1h后，塑性和韧性得到进一步提高，延伸率为50．0％，断面收缩率为55．5％，冲击为68J．材料强度和耐蚀性优于316L不锈钢．     

Effects of chloride ion concentration and pH values on the corrosion behavior of Cr12Ni3Co12Mo4W ultra-high-strength martensitic stainless steel

The effects of Cl- ion concentration and pH values on the corrosion behavior of Cr12Ni3Co12Mo4W ultra-high-strength martensitic stainless steel (UHSMSS) were investigated by a series of electrochemical tests combined with observations by stereology microscopy and scanning electron microscopy. A critical Cl- ion concentration was found to exist (approximately 0.1wt%), above which pitting occurred. The pitting potential decreased with increasing Cl- ion concentration. A UHSMSS specimen tempered at 600°C exhibited a better pitting corrosion resistance than the one tempered at 400°C. The corrosion current density and passive current density of the UHSMSS tempered at 600°C decreased with increasing pH values of the corrosion solution. The pits developed a shallower dish geometry with increasing polarization potential. A lacy cover on the pits of the UHSMSS tempered at 400°C accelerated pitting, whereas corrosion products deposited in the pits of the UHSMSS tempered at 600°C hindered pitting.     

一种微合金化马氏体不锈钢的连续冷却转变研究

用膨胀法结合金相与硬度分析研究了一种新型水轮机叶片用V、N微合金化CrNiMo不锈钢的连续冷却转变行为,获得了该钢的连续冷却转变(CCT)曲线及不同冷却条件下的显微组织和硬度。结果表明,试验用钢的1、3、和温度分别为580℃、730℃、295℃和190℃,其贝氏体和铁素体分别在冷速小于0.5和0.2℃/s时出现,冷速在0.056~0.5℃/s之间时,硬度随着冷速的增大迅速增加,尔后随着冷速的增大,硬度缓慢升高。     

不锈钢钢筋混凝土的应用及发展

基于对不锈钢钢筋化学成分及物理力学性能的介绍,结合有关不锈钢钢筋混凝土的研究成果与工程应用实例,总结了不锈钢钢筋混凝土的特性,并对应用不锈钢钢筋混凝土的工程造价进行了分析,同时介绍了合理使用不锈钢钢筋的一些建议,最后提出了不锈钢钢筋混凝土研究中存在的问题及其发展方向。     

氮含量对0Cr16Ni5Mo马氏体不锈钢高温热变形行为影响

采用Gleeble3800试验机对三种不同N含量的0Cr16Ni5Mo马氏体不锈钢进行等温热压缩实验.通过对真应变-应力曲线及压缩后变形组织的观察,发现相同热变形条件下,N含量的增加提高了试验钢的流变应力,抑制了再结晶晶粒长大.采用Zener-Hollomon参数,以流变应力方程为基础,构建三种本构模型.通过观察拟合应力值与实验值的离散性,确定双曲正弦模型更适用于本试验钢的本构方程计算,优化此计算模型,获得了三种试验钢的本构方程.     

9Cr18不锈钢热变形行为研究

采用Gleeble-1500型热模拟试验机对9Cr18马氏体不锈钢在850～1 150℃、应变速率为0.01～10s-1变形条件下的热压缩变形行为进行研究。根据真应力-应变曲线,分析变形温度和应变速率对9Cr18不锈钢变形抗力的影响,计算其形变激活能,并建立9Cr18不锈钢的变形抗力模型和热变形流变应力方程。结果表明,应变速率一定时,9Cr18动态再结晶临界变形量εc随温度的升高而降低,高的形变温度和低的应变速率有利于动态再结晶的发生;9Cr18不锈钢形变激活能为461.7kJ/mol;所建变形抗力模型的拟合性良好,数据稳定性好。     

Cavitation erosion behavior of WC coatings on CrNiMo stainless steel by laser alloying

The WC powder was precoated on the surface of CrNiMo stainless steel and then made into an alloying layer by using the laser alloying technique. Phases in the layers were investigated by X-ray diffraction (XRD) analysis and surface morphologies after cavitation erosion were observed with the help of scanning electron microscopy (SEM). The cavitation erosion behavior of the CrNiMo stainless steel and WC laser alloying layer in distilled water was tested with the help of ultrasonic vibration cavitation erosion equipment. The results showed that the thickness of the laser alloying layer was about 0.13 mm. The layer had a dense microstructure, metallurgically bonded to the substrate, and no crack had been found. The cavitation erosion mass loss rate of the laser alloying layer was only 2/5 that of the CrNiMo stainless steel. The layer had better cavitation resistance properties because of its metallurgical combination and the strengthening effects of the precipitate phases.