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Effect of electroslag remelting on carbides in 8Cr13MoV martensitic stainless steel  [PDF]
Qin-tian Zhu,Jing Li,Cheng-bin Shi,Wen-tao Yu
- , 2015, DOI: https://doi.org/10.1007/s12613-015-1179-7
Abstract: 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.
Bainitic-martensitic nodular cast iron with carbides  [PDF]
G. Gumienny
Archives of Foundry Engineering , 2010,
Abstract: In this paper the possibility obtaining of upper bainite, lower bainite and martensite or their mixture in nodular cast iron with carbides has been presented. Conditions have been given, when in nodular cast iron with carbides for cooling at first in the form, then air-cooling auste-nite transformation to upper bainite, its mixture with lower bainite and martensite takes place. Transformations proceed during cooling and the crystallization of cast iron have been determined and the casting hardness has been presented.
低碳Si-Mn钢直接淬火-等温配分工艺中组织演变  [PDF]
康健,袁国,张贺,王国栋
- , 2015, DOI: 10.12068/j.issn.1005-3026.2015.01.006
Abstract: 摘要 以低碳Si-Mn钢为研究对象,在传统淬火-配分工艺中引入压缩变形,研究了压缩变形对组织演变的影响以及实验钢在不同等温配分条件下的显微结构特征.结果表明,引入高温变形处理后,试样具有更加精细的显微结构,同时显微组织中含有较高比例的大角度晶界,由无变形条件下的65.7%提高至72.5%;在相变及碳配分过程中,晶界以及板条边界附近易形成碳富集区;随配分时间延长,显微组织呈回火转变趋势,当配分时间延长至1500s时,组织中出现较大量的碳化物析出相,残余奥氏体体积分数降低至7.9%.
Abstract:Compression deformation was introduced into the conventional quenching and partitioning process for low carbon Si-Mn steel.Effects of the hot deformation on microstructure evolution and microstructure characteristics of specimens treated by various isothermal partitioning processes were investigated. The results showed that the microstructure is refined and the fraction of high-angle grain boundary increases from 65.7% to 72.5% due to the hot deformation. Carbon-rich areas formed during transformation and partitioning process are mostly observed at the boundaries of prior austenite grains and martensite laths. With the increase of the partitioning time,the microstructure shows a tendency to tempering transformation. When the partitioning time is up to 1500s, a great number of carbides are formed and the volume fraction of retained austenite decreases to 7.9%.
CARBIDES IN STEEL 4335 V
4335V钢中碳化物的研究

ZHONG Jiaxiang,ZHENG Xiuhua,XU Zongrui,BAI Dezhong Beijing University of Science,Engineering Nei Monggol Machine Works No,
钟家湘
,郑秀华,徐宗瑞,白德忠

金属学报 , 1989,
Abstract: 实验表明,4335V钢淬火回火后析出三种碳化物:(1)M_3C,在200至700℃回火时析出,其中溶有Cr,Mn,Mo,V,随回火温度升高,Cr含量从2.6%增至19.5%;(2)M_7C_3,在400℃以上回火时析出,其中含Cr20—30%,还溶有Mn和Mo;(3)M_4C_3,在高于500℃回火时析出,其中M为V,Mo,Cr,其原子比为V:Mo:Cr≈7:1:1。 本文还研究了碳化物的形貌和分布特征,以及与淬火亚结构的关系,初步分析了它们对钢的低温冲击韧性的影响。
低碳双相钢冲击韧性及断裂特征  [PDF]
冯凯,赵伟毅,洪班德
材料工程 , 1990,
Abstract: 本文研究了低碳双相钢中不同体积百分比及不同强度比的铁素体、马氏体双相组织对钢的冲击韧性及断裂过程的影响。结果表明马氏体数量增加使钢的韧性降低,回火温度升高使钢的韧性提高。冲击断口形貌由室温的韧窝型转变为-78℃时以准解理为主及-196℃时全部解理型。
Al对淬回火H11钢力学性能和碳化物的影响 Influence of Al on mechanical properties and carbides of quenched and tempered H11 steel  [PDF]
张国文,左鹏鹏,何西娟,盛振栋,吴晓春
- , 2018,
Abstract: 研究了Al质量分数为0.77%及不含Al的H11钢在不同淬回火处理工艺下的硬度和冲击功的变化规律,并对两种钢原始退火态、1060℃淬火、1060℃淬火+510℃回火、1060℃淬火+560℃回火和1060℃淬火+600℃回火处理后的试样进行碳化物萃取,同时借助扫描电子显微镜(SEM)和X射线衍射仪(XRD)分析了Al对H11钢中碳化物形态及类型的影响.结果表明:(1)Al能提高H11钢的冲击韧性和回火硬度,但会使淬火硬度有所降低.(2)Al可以促进H11钢淬火过程中碳化物的溶解和元素的均匀分布.(3)Al会阻碍H11钢回火过程中碳化物的析出和聚集,这种作用在560℃以下回火时更加显著.(4)Al可以使H11钢回火时的(Fe,Cr)2C、Mo C、Cr7C3类碳化物更加稳定,抑制(Fe,Cr)3C、Mo2C和Cr23C6类碳化物的析出,这是因为Al可以阻碍H11钢中碳及合金元素在回火过程中的聚集.
低碳马氏体钢的透射电镜分析  [PDF]
谈育煦
金属学报 , 1985,
Abstract: 本文用透射电子显微镜研究了具有代表性的六种低碳马氏体钢的显微组织,结果表明含碳量较低的马氏体钢(指0.1—0.25wt-%C),淬火后一般都存在薄膜状残余奥氏体,低碳马氏体钢淬火时不可避免有自回火现象,自回火沉淀出的碳化物是六方晶格的ε碳化物,六种钢都能找到具有局部孪晶亚结构的板条晶,低碳马氏体在350—400℃回火时,ε转化成Fe_3C;回火温度提高至500℃时,孪晶消失,但马氏体板条晶的轮廓在600℃时仍可维持原状.
Nanostructure of a cold drawn tempered martensitic steel  [PDF]
Xavier Sauvage,Xavier Quelennec,Jean-Jacques Malandain,Philippe Pareige
Physics , 2006,
Abstract: The carbon atom distribution in a tempered martensitic steel processed by cold drawing was investigated with a three-dimensional atom probe. Data clearly show that cementite starts to decompose at the early stage of deformation. This indicates that the driving force of cementite decomposition during plastic deformation is not related to a strong increase of the interfacial energy. Carbon atmospheres were also analysed. They probably result from pipe diffusion of carbon atoms along dislocations pined by Fe3C carbides.
氮离子注入钢表面碳层的研究  [PDF]
余镇江,杨得全,谢燮,阎荣鑫,范垂祯
金属学报 , 1989,
Abstract: 本文对四种相同能量、不同剂量氮离子注入的GCr15钢表面形成的石墨碳层进行了Auger研究。Auger剖面谱图的结果表明此碳层厚度与氮离子的注入剂量成正比。与摩擦磨损实验结果比较,发现摩擦系数在随时间变化曲线的初期,小于0.20,即离子注入过程中钢表面形成的碳层有助于减小摩擦系数。
含碳纳米管二相流体润滑剂对钢-钢接触疲劳性能的影响  [PDF]
宋宝玉,曲建俊,张锋,殷玉龙,齐毓霖
摩擦学学报 , 2003,
Abstract: 制备了含碳纳米管的二相流润滑剂,利用自制的球-棒疲劳试验机研究了碳纳米管对钢球接触疲劳寿命的影响;利用扫描电子显微镜分析了碳纳米管抗滚动接触疲劳机理.结果表明:与基础油相比,含1%质量分数碳纳米管的二相流体润滑剂可以使钢球的接触疲劳寿命L10提高3倍以上;当碳纳米管含量增加到3%时,钢球的接触疲劳寿命基本保持不变;利用微粒吸附模型和微粒垫衬模型可以较好地解释碳纳米管提高钢球接触疲劳寿命的原因.
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