无莱氏体高速钢2W－3Mo－4Cr－6V

在本文作者研制的有别于基体钢，低碳高速钢和普通渗碳高速钢的新型无莱氏体高速钢的基础上，又成功地研制成一种高Ｖ无莱氏体高速钢２Ｗ－３Ｍｏ－４Ｃｒ－６Ｖ。该钢经热处理后硬度高于７０ＨＲＣ，６００℃红硬性为６７．５ＨＲＣ。用其制成Ｍ３３挤压丝锥的使用寿命较１８Ｗ－４Ｃｒ－Ｖ丝锥高２倍。     

25W3Mo4Cr2V7Co5钢过饱和渗碳的碳化物及性能

研制的２５Ｗ３Ｍｏ４Ｃｒ２ＶＣｏ５高韧高硬高速钢的共晶碳化物尺寸平均为２－４μｍ，最大约为８μｍ；经最佳规范过饱和渗碳后碳化物尺寸平均为４－６μｍ，最大亦仅为１０μｍ。热处理后的硬度可达ＨＲＣ６７－７０，用该钢制造的车刀，其耐用度显著高于Ｗ１８Ｃｒ４Ｖ钢。     

D542钢中碳化物的电镜研究

Ｄ５４２钢是我所研制的一种无钨低合金高速钢。它在平衡状态下不发生共晶反应，是一种过共析高速钢，本文用ＴＥＭ研究了Ｄ５４２钢铸态，退火态和回火态的碳化物。结果和分析表明：Ｄ５４２钢铸态中碳化物类型主要是Ｍ７Ｃ３，Ｍ３Ｃ，Ｍ２３Ｃ６等，没有发现莱氏体高速钢中共晶碳化物的主要类型Ｍ６Ｃ０。该钢二次硬化的主要特殊碳化物同Ｍ２Ｃ型碳化物。     

Ti,N,Mg对M2高速钢凝固组织和硬度的影响

为了改善Ｍ２高速钢共晶碳化物的分布，本文利用小凝固试样变质的方法研究了Ｔｉ，Ｎ和Ｍｇ对Ｍ２高速钢凝固组织和硬度的影响。试验结果表明，加入Ｔｉ或Ｔｉ－Ｎ后，共晶碳化物形态和分布有很大改善，而加入Ｔｉ－Ｎ后对凝固组织有轻微的细化作用，但只添加Ｔｉ不补碳时，钢的淬火硬度和回火硬度均下降；加入适量的Ｍｇ可以使片状的Ｍ２Ｃ型共晶碳化物转为鱼骨状的Ｍ６Ｃ型共晶碳化物，使其分布有所改善，Ｔｉ和Ｍｇ复合加入可以明     

低合金高性能高速钢中的碳化物及其对刀具切削寿命的影响

研究了Ｗ４Ｍｏ３Ｃｒ４ＶＳｉ低合金高性能高速钢的碳化物数量及成分特点，发现此钢的一次碳化物数量明显少于Ｍ２钢，而二次硬化碳化物中铬含量比Ｍ２钢高。文中对比分析了Ｗ４Ｍｏ３Ｃｒ４ＶＳｉ和Ｍ２钢的的二次硬化碳化物析出能力，并根据一次，二次硬化碳化物对高速钢切削寿命的贡献说明了Ｗ４ＭｏＣｒ４ＶＳｉ钢利用合金成分设计，在大大节约贵重合金元素Ｗ，Ｍｏ的条件下获得与通用高速钢相当的切削寿命的原因。     

钢中的钒

钒在钢中的作用与它的强碳化物构成能力和其沉淀浓度或在铁素体－珠光体和马氏体中二次硬化反应的产生有关系。以前，它作为一种微量合金（〈０．２％），但当钒加入到０．７５％时，它就进入铁素体形成蠕变稳定钢；当它出现有高速钢中时，它的浓度已经达到或超过１％。这篇文章再次考察了这些钢的冶金学，重点任务放在Ｖ与其它碳化物构成元素如Ｎｉ、Ｔｉ、Ｃｒ和Ｍｏ的关系。     

高钴,镍超高强度钢的二次硬化行为

利用透射电子显微术（ＴＥＭ）研究了一种高钴、镍超高强度钢不同时效温度下的碳化物的析了过程及钢的二次硬化机制。研究结果表明，马氏体板条内和板条间开始析出合金碳化物Ｍ２Ｃ的初始回火温度为４００℃左右；４４０℃温度回火钢的二次硬化行为是由于合金碳化物Ｍ２Ｃ对尚未回复和再结晶的位错型马氏体板条弥散强化的结果；６５０℃过时效后在钢的回火组织中还发现了一种正交结构的碳化物相，其点阵常数α＝０．４４８ｎｍ，ｂ＝     

稀土元素对热轧辊用钢60CrMnMo热疲劳性能的影响

本文研究了稀土元素对热轧辊用钢６０ＣｒＭｎＭｏ热疲劳性能的影响，同时对不同稀土含量的６０ＣｒＭｎＭｏ钢高温短时拉伸性能和硬度进行了比较。试验结果表明：稀土元素可明显提高６０ＣｒＭｎＭｏ钢的热疲劳寿命和塑性，抑制６０ＣｒＭｎＭｏ钢的循环软化，并得出稀土元素的合适含量为０．０５％－０．１０％。     

高速钢的组织超细化与超塑性变形力学行为

研究了Ｗ６Ｍｏ５Ｃｒ４Ｖ２高速钢的超细化热处理工艺和超塑变形力学行为。结果表明，该钢在１０４０℃两次循环淬火是实现其超细化的最佳热处理工艺；按此工艺进行预处理后，在８１０℃、初始应变速率为３．３３×１０＾－４ｓ＾－１的最佳变形条件下，该钢的超塑伸长率可达１９２％，流变应力为５８ＭＰａ，应变速率敏感性指数（ｍ）为０．２７。     

铁素体—珠光体钢组织和性能关系

本文对含０．０６５％￣０．２２％Ｃ、０．００２￣０．０２１％Ｓ、０．６￣１．５％Ｍｎ、０．０２￣０．４％Ｓｉ（重量百分数）系列钢（普通Ｃ－Ｍｎ、Ｃ－Ｍｎ－Ａｌ、Ｃ－Ｍｎ－Ｎｂ－Ａｌ钢）进行了研究，大多数此类钢经常化处理，以８００￣４００℃的平均冷却速率在４０￣０．８Ｋｍｉｎ＾－１变化。这相当于１２￣５００ｍｍ厚板在空气中冷却的速率。一些高温奥氏体化处理随后炉冷的钢产生粗铁素体晶粒和粗晶界碳化物。得     

Effects of alternating magnetic field on hardness of W6Mo5Cr4V2 high- speed steel cutting tool

In order to study the effect of alternating magnetic field on the hardness of W6Mo5Cr4V2 high- speed steel cutting tool, the influence of different magnetic field frequency and magnetic time on the hardness of high- speed steel cutting tool was studied by the self- made magnetized experiment platform, using the Origin software to draw a magnetic hysteresis curve of W6Mo5Cr4V2 materials, the magnetization of ferromagnetic materials was further analyzed. The experimental results show that: under the low frequency magnetization condition of the magnetization parameter of 10Hz, the hardness of high speed steel cutting tool improves 4. 58HRC; the rate of hardness change at magnetization time of 30s is 4. 54% higher than that at magnetization time of 120s; alternating magnetic field processing can improve the dispersion carbide content of the tool, reinforce materialistic matrix, improve the hardness of high speed steel tool.     

Effect of RE－Al－N on Structures and Properties of M2 Cast High Speed Steel

M 2highspeedsteel (M 2steel)isamaterialwidelyusedintoolsanddies[1,2 ] .M 2steelischarac terizedbyalongsolidificationrangeandcomplexeu tecticreactions ,whichresultsinsegregationofalloy ingelementsandformationofseveraldifferenttypesofcarbidesduringsolidification[3,4 ] .Forconventionallyprocessedhigh speedsteels ,itisinevitablethatacoarsecarbidenetworkwillbeformedduringsolidifi cation .Coarseprimarycarbidestendtoresultinun evencarbidebandsdistributionafterasubstantialamountofhotprocessing[5] .Ma…     

Microstructure and Mechanical Properties of Martensitic Stainless Steel 6Crl5MoV

 Martensitic stainless steel containing Cr of 12% to 18% (mass percent) are common utilized in quenching and tempering processes for knife and cutlery steel. The properties obtained in these materials are significantly influenced by matrix composition after heat treatment, especially as Cr and C content. Comprehensive considered the hardness and corrosion resistance, a new type martensitic stainless steel 6Cr15MoV has been developed. The effect of heat treatment processes on microstructure and mechanical properties of 6Cr15MoV martensitic stainless steel is emphatically researched. Thermo-Calc software has been carried out to thermodynamic calculation; OM, SEM and TEM have been carried out to microstructure observation; hardness and impact toughness test have been carried out to evaluate the mechanical properties. Results show that the equilibrium carbide in 6Cr15MoV steel is M23C6 carbide, and the M23C6 carbides finely distributed in annealed microstructure. 6Cr15MoV martensitic stainless steel has a wider quenching temperature range, the hardness value of steel 6Cr15MoV can reach to HRC 608 to HRC 616 when quenched at 1060 to 1100 ℃. Finely distributed carbides will exist in quenched microstructure, and effectively inhabit the growth of austenite grain. With the increasing of quenching temperature, the volume fraction of undissolved carbides will decrease. The excellent comprehensive mechanical properties can be obtained by quenched at 1060 to 1100 ℃ with tempered at 100 to 150 ℃, and it is mainly due to the high carbon martensite and fine grain size. At these temperature ranges, the hardness will retain about HRC 592 to HRC 616 and the Charpy U-notch impact toughness will retain about 173 to 20 J. A lot of M23C6 carbides precipitated from martensite matrix, at the same time along the boundaries of martensite lathes which leading to the decrease of impact toughness when tempered at 500 to 540 ℃. The M3C precipitants also existed in the martensite matrix of test steel after tempered at 500 ℃, and the mean size of M3C precipitates is bigger than that of M23C6 precipitates.     

淬火温度对M4粉末高速钢组织和性能的影响

为了研究淬火温度对M4粉末高速钢组织和性能的影响, 利用光学显微镜观察高速钢试样的金相组织, 对淬火组织的晶粒度进行评级, 并对回火组织中碳化物的组成和分布进行统计; 采用洛氏硬度计和材料万能试验机测试试样的硬度和抗弯强度。结果表明: 随淬火温度的升高, M4粉末高速钢淬火后硬度先上升后下降, 在1200 ℃时出现最大值HRC62.9;淬火态试样的晶粒度随淬火温度的升高而降低。经三次回火后M4粉末高速钢硬度值较淬火态均有提高, 且随淬火温度的升高, 先增高后下降, 在淬火温度为1190 ℃时达到最大值HRC66.4。随淬火温度的升高, 回火态试样的抗弯强度逐渐下降, 碳化物聚集长大倾向明显, 尺寸均匀性下降。M4粉末高速钢的最优淬火温度区间为1180~1190 ℃。     

注射成形M4高速钢的研究

研究了惰性气体雾化法制备的M4高速钢合金粉末进行注射成形工艺,由于粉末颗粒球形度和流动性好,粉末装载量可以达到70%(体积分数),注射料表现假塑性流体的特性。注射坯采用溶剂脱粘+后续热脱粘工艺进行脱粘,总共脱粘时间为14h。在氮气气氛中1250℃烧结2h,可以制备出烧结态硬度为HRC57~59的高速钢材料,热处理后材料的硬度可达HRC64~65。微观结构分析表明,PIM高速钢组织均匀,富钨M6C碳化物和富钒M(C,N)碳氮化物弥散分布在高速钢基体中。     

Effect of Mischmetal on As-cast Microstructure and Mechanical Properties of M2 High Speed Steel

High speed steel has been widely used in various fields due to their excellent red hardness and good wear resistance.However,the influence of mischmetal(Ce-La)on the as-cast microstructures and mechanical properties of high speed steel has rarely been reported.Thus,the microstructure and mechanical properties of M2 high speed steel with addition of mischmetal(Ce-La)were investigated.The morphology and distribution of the eutectic carbides of the steel were observed by using optical microscopy and scanning electron microscopy,and the impact toughness and bending strength were tested.The results show that adding mischmetal has an obvious effect on the microstructure and mechanical properties of M2 high speed steel.The coarse eutectic structure is refined,the weak connection of the carbide networks is broken and the flake carbides become short and fine.More networks of eutectic carbides dissolve into the matrix.When a suitable adding content of mischmetal is selected,for example,0.3mass%,the impact strength and bending strength can increase by 27% and 10.76% compared with that without mischmetal,respectively.     

高氮不锈轴承钢的微观组织与性能研究

利用OM、SEM、XRD和电化学方法对X60N高氮不锈轴承钢(/％:0.63C,15.00Cr,0.61Mo,0.190N)进行组织观察、室温和高温力学性能及耐蚀性能研究.结果表明,钢中降碳加氮可显著降低粗大共晶碳化物的数量及尺寸,X60N钢加氮后的原始奥氏体晶粒尺寸及碳化物明显细化.X60N钢经1050 ℃奥氏体化淬...     

高氮不锈轴承钢中的碳氮化物对力学性能的影响

 440C等高碳马氏体轴承钢中由于存在大量粗大的共晶碳化物,降低其耐蚀性和疲劳性能,影响了其广泛应用。40Cr15Mo2VN作为一种新型高氮不锈轴承钢,通过降低碳含量,增加氮含量和微合金化来改善其性能。氮的加入一方面析出细小弥散的氮化物,强化了基体;另一方面改善了钢中析出的碳化物的形态、尺寸和分布,使其由原来的带状和网状连续分布变为近圆形颗粒,最大碳化物尺寸由原来的70μm以上减小到小于18μm,弥散分布,从而使Rm达到2000MPa以上,ReL达到1700MPa以上,有些超过1800MPa,表面硬度≥585(HRC),U型缺口冲击功保持在8J以上,并具有优异的耐蚀性和疲劳性能,满足轴承钢的服役要求。     

热处理工艺对F550海洋平台用钢组织与性能的影响

通过对不同淬火、回火工艺处理后的F550海洋平台用钢的力学性能、断口形貌、微观组织等进行分析,探讨了淬火、回火工艺参数对钢板性能及组织的影响。结果表明,淬火温度越高,组织晶粒越细小;随回火温度的升高,组织粗化,位错密度减少,钢板强度降低,塑性和韧性提高。16mm厚F550钢板最佳调质工艺为:880℃×120min淬火,630℃×220min回火。调质处理后钢板组织为粒状贝氏体+少量板条铁素体,屈服强度580MPa,抗拉强度660MPa,断后伸长率23%,-60℃冲击功稳定在210J以上。     

钢管及冷弯型钢用高性能铸造轧辊的研制开发

以高碳、高铬、高镍、高钼为特征,采用多元合金变质强化,通过铸造、热处理和机加工,山东省四方技术开发有限公司开发出了高性能高铬辊。材料基体组织为奥氏体、贝氏体或马氏体,碳化物主要是M7C3,含量20%左右,显微硬度可达HM1800,并呈不连续的条块状、颗粒状和菊花状。抗拉强度540MPa,冲击韧性7.5J/cm2,距表面120mm处硬度达HRC59.3。用于矫直辊及焊管轧辊,材料利用率达77.5%以上。同时指出,轧辊制造的发展趋势是高性能、高合金化、以铸代锻及双金属结构等。