稀土Y离子注入对形成不同类型氧化膜合金的高温抗氧化性能的影响

：研究了稀土Ｙ离子注入对ＦｅＣｒ,ＦｅＣｒＡｌ及ＮｉＣｒ合金高温抗氧化性能的影响。结果表明,对于主要形成Ｃｒ２Ｏ３膜的ＦｅＣｒ和ＮｉＣｒ合金,通过离子注入Ｙ可以明显提高其高温抗氧化性能,但对形成Ａｌ２Ｏ３膜的ＦｅＣｒＡｌ合金,离子注入对合金抗氧化性能没有影响,添加稀土Ｙ则使ＦｅＣｒＡｌ合金抗氧化性能大大提高。分析了氧化前、后氧化膜结构变化,认为早期形成的Ｙ２Ｏ３膜对高温氧化时金属离子的扩散有不同的影响     

含碳铬矿球团还原热力学研究

本文介绍了含碳西藏铬矿球团的还原顺序。Ｘ射线衍射证明：还原温度低于１２００℃时，还原产物是Ｆｅ及Ｃｒ_２Ｏ_３；还原温度高于１２００℃时，还原产物是Ｆｅ、Ｆｅ_３Ｃ、（Ｃｒ，Ｆｅ）_７Ｃ_３，在还原初期阶段生成的Ｆｅ转变成Ｆｅ_３Ｃ_，最终转变成（Ｃｒ，Ｆｅ）_７Ｃ_３；当还原温度高于１３００℃时，发现有ＭｇＡｌ_２Ｏ_４，ＭｇＳｉＯ_４生成，热力学计算的结果与Ｘ射线衍射结果相符。     

工业硅中金属间化合物

工业硅是在工业电炉内由石英和不同的炭质还原剂生产的．含有高达１％金属杂质。这些金属杂质就是聚集在晶粒边界的硅的化合物，在凝固期间在工业硅中形成的沉淀物。用具有波长色散的Ｘ射线分析扫描电子显微镜，我们鉴定了多达十种二元、三元、四元甚至多元化合物。用这种方法研究了富硅区金属间化合物的物理和化学性质。它们是Ｓｉ２Ｃａ、Ｓｉ２Ａｌ２Ｃａ、Ｓｉ８Ａｌ６Ｆｅ４Ｃａ、Ｓｉ２ＦｅＴｉ，Ｓｉ７Ａｌ８Ｆｅ５、Ｓｉ２Ａｌ３Ｆｅ和Ｓｉ２Ｆｅ（Ａｌ）。根据含有杂质的比例，我们确定了工业硅中每种化合物在给定的冷却条件下存在的区域，计算了平衡相图，以了解固化机理。一些实验表明，计算值和实验值吻合良好。为了确定硅的一个较好的生产方法，我们探讨了金属间化合物在氯甲基化反应上的影响。实验数据显示了冷却条件在金属间化合物稳定性方面的响响。例如，硅在９００℃缓冷，按照反应３Ｓｉ２Ａｌ２Ｃａ＋４Ｓｉ２Ｆｅ→４Ｓｉ２Ａｌ６Ｆｅ４Ｃａ＋２Ｓｉ２Ｃａ＋２Ｓｉ则四元金属间化合物Ｓｉ８Ａｌ６Ｆｅ４Ｃａ大量增加，而三元化合物消失。相图和不平衡反应知识加深了对固化机理以及各种组分和冷却条件下硅的行为的了解．硅的结构和控制结构的参数知识使人们了解硅的特点和改变它的     

喷射沉积Al-Si-Fe-Cu-Mg合金中的相组成

对喷射沉积快速凝固Ａｌ－Ｓｉ－Ｆｅ－Ｃｕ－Ｍｇ合金的相组成进行了分析。结果表明：合金中含有α－Ａｌ、β－Ｓｉ、δ（ＦｅＳｉ２Ａｌ４）、Ａｌ８Ｓｉ６Ｍｇ３Ｆｅ和β（Ｆｅ２Ｓｉ２Ａｌ９）等相;初晶硅相呈颗粒状,共晶硅相和δ（ＦｅＳｉ２Ａｌ４）呈细小的片状,Ａｌ８Ｓｉ６Ｍｇ３Ｆｅ相呈细小的颗粒状;经Ｔ６工艺热处理后,新析出Ａｌ２Ｃｕ相,Ａｌ８Ｓｉ６Ｍｇ３Ｆｅ相数量增加,少量δ（ＦｅＳｉ２Ａｌ４）转化为β（Ｆｅ２Ｓｉ２Ａｌ９）。     

钢包炉（LF）CaO－SiO_2－MgO－Al_2O_3渣系的脱硫试验

钢包炉（ＬＦ）ＣａＯ－ＳｉＯ_２－ＭｇＯ－Ａｌ_２Ｏ_３渣系的脱硫试验郭上型，万真雅（华东冶金学院，马鞍山２４３００２）ＤｅｓｕｌｐｈｕｒｉｚｉｎｇＴｅｓｔｕｓｉｎｇＣａＯ－ＳｉＯ_２－ＭｇＯ－Ａｌ_２Ｏ_３ＳｌａｇｉｎＡＬａｄｌｅＦｕｒｎａｃｅ￥ＧｕｏＳ...     

英国基准Fe_2O_3和国产基准Fe_2O_3的对比试验

英国基准Ｆｅ２Ｏ３和国产基准Ｆｅ２Ｏ３的对比试验①昆明冶金研究院②王建琴采用硫磷混酸溶样，ＳｎＣｌ２－ＨｇＣｌ２－Ｋ２Ｃｒ２Ｏ７〔或Ｃｅ（ＳＯ４）２〕体系滴定法测定铁，由于有很高的准确度，至今仍是测定高含量铁的主要方法之一。经验表明，用基准的Ｋ２Ｃｒ...     

高碱度控制氧位渣系（BaO—BaCl2—Cr2O3）对含铬铁水选择氧化脱磷影响的研究

在实验室条件下，以小渣量研究了ＢａＯ－ＢａＣｌ２（或ＢａＦ２）－Ｃｒ２Ｏ３系脱磷剂对高铬铁水脱磷时，脱磷剂中溶剂（ＢａＣｌ２和ＢａＦ２），氧化剂（Ｃｒ２Ｏ３和Ｆｅ２Ｏ３），渣量，铁液中原始〔％Ｃ〕和〔％Ｓｉ〕，以及温度对脱磷率的影响。     

高碱度控制氧位渣系（BaO－BaCl_2－Cr_2O_3）对含铬铁水选择氧化脱

在实验室条件下，以小渣量研究了ＢａＯ－ＢａＣｌ＿２（或ＢａＦ＿２）－Ｃｒ＿２Ｏ＿３系脱磷剂对高铬铁水脱磷时，脱磷剂中溶剂（ＢａＣｌ＿２和ＢａＦ＿２）。氧化剂（Ｃｒ＿２Ｏ＿３和Ｆｅ＿２Ｏ＿ｓ）、渣量、铁液中原始（％Ｃ）和（％Ｓｉ），以及温度对脱磷率的影响。     

FeNiCrAlRE高温耐热合金研制

从Ｆｅ－（８～４０）Ｎｉ－（１０～３０）Ｃｒ－（３～８）Ａｌ合金中筛选出３种γ相合金，它们的抗氧化性与ＦｅＣｒＡｌ合金相同，热强性，抗脆化能力与塑性与Ｃｒ２０Ｎｉ８０合金相当，而且有良好的铸造，冷加工和焊接性能，合金生产成本只有Ｃｒ２０Ｎｉ８０的１／３，在耐热和电热领域有重要的应用前景，选出了２种γ＋α双相合金，与ＦｅＣｒＡｌ合金相比，其抗氧性相同，热强性和抗脆化能力略高，塑性稍低，可用于高使用温     

三价铁离子介质中硫化银的浸出

用转盘技术研究了合成Ａｇ２Ｓ在ＦｅＣｌ３－ＨＣｌ和Ｆｅ２（ＳＯ４）３－Ｈ２ＳＯ４介质中的浸出。在ＦｅＣｌ３－ＨＣｌ介质中，温度为４０－９５℃的范围内，Ａｇ２Ｓ较快地溶解，且随之主要形成元素硫。溶解动力学始终服从抛物线速率定律。速率与转盘速度无关，也与ＦｅＣｌ２浓度（当＞０．０３ｍｏ．／Ｌ时）无关。     

碳化铬/Ni_3Al复合材料的室温微动磨损性能

对比研究了碳化铬/Ni3Al复合材料和传统高温耐磨材料Stellite 6合金和T800合金的室温耐微动磨损性能。结果表明,碳化铬/Ni3Al复合材料具有优异的耐微动磨损性能,与GCr15对磨时,其室温相对耐磨性分别是Stellite 6和T800合金的5.5倍和2.6倍。通过分析微动磨损机制认为,碳化铬/Ni3Al复...     

热等静压Cr3 C2/Ni3 Al复合材料的微观组织及相组成

采用热等静压技术(HIP)在1160℃、100 MPa 条件下制备出 Cr3 C2/Ni3 Al 复合材料,研究了 Cr3 C2/Ni3 Al复合材料的微观组织和相组成。结果表明,Cr3 C2初始颗粒首先溶解成 Cr 和 C 原子,并往基体中扩散;冷却过程中,溶解的Cr和C原子转化为稳定的Cr7 C3结构;由于 Ni3 Al合金中的 Fe易与 C形成稳定碳化物,促使Fe原子从基体中往Cr7 C3结构中发生上坡扩散,并取代Cr7 C3结构中的部分Cr原子形成 M7 C3(M为 Cr、Fe,余同)结构的扩散相。当Cr3 C2初始颗粒较大时,在高温过程中,Cr3 C2颗粒未能全部溶解,而未溶解的 Cr3 C2颗粒芯部在冷却过程中仍保持为Cr3 C2结构。该条件下制备的Cr3 C2/Ni3 Al复合材料主要由Cr3 C2硬芯相、M7 C3扩散相和γ′-Ni3 Al基材相组成,其中Cr3 C2硬芯相和γ′-Ni3 Al基材相通过M7 C3扩散相形成良好的扩散连接;该结构的复合材料磨损后表面Cr3 C2颗粒末发生剥落且沟槽在铬碳化物处发生中断,表现出良好的耐磨性。     

Development of New Wear-Resistant Surface Coating at Elevated Temperature

Metal matrix composites containing a high vol-ume fraction of carbide particles are frequently usedas wear-resistant materials[1 -4]. For elevated tem-perature service in air ,the oxidation resistance andthe hot hardness of hard particle are the most i mpor-tant factors .In metal carbides ,tungsten carbide andchromiumcarbide can act as hard particles in metalmatrix in order to increase their hot hardness andthe ability of wetting metal matrix. Compared withtungsten carbide ,chromiumcarbide is …     

High Temperature Phase Stability and Microstructural Characterization of D9 Stainless Steel-Zirconium Metal Waste Form Alloys

Zirconium present in stainless steel-zirconium metal waste form (MWF) alloys form Ni?CZr and Fe?CZr intermetallic phases which act as a sink for radionuclide and improve resistance to localized corrosion as well as selective radionuclide leaching. The present study looks into the behavior of Zr intermetallics in MWF alloys with the variation of Zr content after heat treatments. Two MWF alloys of D9 SS (Ti modified 15Cr?C15Ni?C2.5Mo stainless steel) with 8.5 and 17?wt% Zr were heat treated at 1,323?K for 2 and 5?h and characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The stability of the Zr intermetallic compounds was examined by high temperature XRD. The results from XRD study showed the presence of NiZr, Ni₅Zr, Ni₇Zr₂, FeZr₂, and Fe₃Zr peaks along with fcc Fe based solid solution. The MWF alloy with 17?wt% Zr exhibited ??-ferrite peak in as-cast condition which was not observed after heat treatment. From the SEM micrograph the agglomeration of intermetallic phases was observed after heat treatment and the grain size of the intermetallic phases increased with duration of heat treatment. The high temperature XRD study revealed that all the intermetallic phases were stable up to 1,173?K and above this temperature Ni?CZr intermetallics started disappearing. However Fe?CZr intermetallics were stable till 1,373?K. The paper presents the high temperature phase stability of D9 SS-Zr MWF alloys.     

Microstructure and Properties of Fe–Cr–B–Al Alloy After Heat Treatment

By means of optical microscope, scanning electron microscope, X-ray diffraction, energy dispersive spectrometer, Rockwell and Vickers hardness tester, and wear tester, the microstructure and properties of Fe–10Cr–1B–4Al alloy quenched in different temperature has been studied. The results show that the microstructure of as-cast Fe–10Cr–1B–4Al are composed of pearlite, ferrite and the eutectic borocarbide which shows a network distribution along grain boundaries. The eutectic borocarbides are composed of M₇(C, B)₃, M₂(B, C) and M₂₃(C, B)₆. As the quenching temperature increases, the network structure of eutectic borocarbide breaks, but the type of eutectic borocarbide has no obvious change, and the matrix structure changes gradually from ferrite to pearlite. As the quenching temperature increases, the macro-hardness and the matrix micro-hardness of Fe–10Cr–1B–4Al alloy increases gradually. The macro-hardness and matrix micro-hardness of alloy reach the highest value of 45.7 HRC and 388.1 HV, respectively when the quenching temperature is 1150 °C. The hardness of alloy decreases slightly when the quenching temperature is too high. While quenching at 1150 °C, the alloy has the highest wear resistance and good comprehensive properties.     

Al含量对WC-Co硬质合金耐腐蚀性能的影响

研究了Al对WC—Co硬质合金耐腐蚀和抗高温氧化性能的影响。结果表明，在WC-Co中加入的Al与Co形成Co-Al金属间化合物，使粘结相的结构和性能发生根本性的改变。溶液腐蚀、极化曲线测试以及高温氧化实验表明，在一定的范围内增加Al含量可以提高合金的耐腐蚀性能和抗高温氧化性能，粘结相中w（Al）为8％时合金的耐腐蚀性能达到最佳，w（Al）为6％时抗高温氧化性能达到最佳。     

纳米WC增强Ni基合金喷熔层在不同介质中抗泥浆冲蚀性能研究

采用氧乙炔火焰喷熔工艺制备了Ni60CuMo和纳米WC增强Ni60CuMo两种Ni基合金喷熔层,采用XRD、SEM方法分析了喷熔层的组织结构,测量了喷熔层的硬度和电化学性能;研究了两种喷熔层在淡水和3.5wt.%NaCl介质中的抗泥浆冲蚀磨损性能。结果表明,纳米WC增强Ni60CuMo合金喷熔层的组织结构为纳米WC呈块状均匀镶嵌在γ相固溶体和Cr23C6、Cr7C3等硬质相之间,形成弥散强化,使其硬度提高了约13%;纳米WC增强的Ni基合金喷熔层在3.5wt.%NaCl介质中比Ni60CuMo喷熔层具有更低的腐蚀电位与更高的腐蚀电流密度,它在淡水和3.5wt.%NaCl介质中的抗泥浆冲蚀磨损性能分别比Ni60CuMo喷熔层提高了约53%和20%。纳米WC的加入显著提高了Ni基合金喷熔层的抗泥浆冲蚀性能,但在3.5wt.%NaCl介质中,由于WC与NiCr合金之间形成了大量微电池,加速了喷熔层的腐蚀磨损,使其抗泥浆冲蚀性能的增强效果受到削弱。     

Improving High‐Temperature Wear Resistance of Fe–Cr13–C Hardfacing Alloy by Nitrogen Alloying

Nitrogen alloying of Fe–Cr13–C hardfacing alloy produces marked precipitation strengthening to achieve an improvement in high‐temperature wear resistance. Two hardfacing alloys of Fe–Cr13–C (with and without nitrogen) are slid on carbon steel at high‐temperature of 600°C and high load of 600 N, and wear behaviors are studied systematically. It is found that abrasive wear occurrs on the surface of the hardfacing alloy due to abrasive action of crushed oxide particles coming from the surface of carbon steel on the high temperature. The wear resistance is determined by the size and distribution of precipitates. The results show that the hardfacing alloy can obtain a great increase in hardness and a marked decrease in wear depth of grooving due to the effect of carbonitirde precipitates. The high‐temperature wear resistance of the Fe–Cr13–C hardfacing alloy is improved by nitrogen alloying, and the wear mechanism is mainly plastic deformation with minimum depth of grooving caused by the oxide particles.     

钴铁镍复合黏结相超细硬质合金显微组织与性能

钴作为硬质合金应用最广泛的黏结剂,存在资源稀缺、成本高昂以及WC-Co硬质合金耐腐蚀性能较差等问题,综合考量生产成本与改善性能,本研究采用铁镍部分代替钴组成复合黏结剂,以其制备超细硬质合金,研究其显微组织和力学、耐蚀耐磨性能的关系。结果表明,黏结相中Fe/Ni质量分数比增加,使得合金WC晶粒细化和黏结相分布不均,合金的硬度和抗弯强度分别提高与降低。合金在中性NaCl溶液中的耐腐蚀性能评估采用极化曲线测试与浸泡实验,黏结相添加Ni能提高合金耐蚀性,归因于Ni的钝化特性与促进腐蚀产物膜的形成。硬质合金摩擦系数和磨损率与Fe/Ni质量比呈负相关,合金耐磨性的提高主要归因于黏结相的强度增强和WC晶粒细化合金硬度提高。