共查询到18条相似文献,搜索用时 78 毫秒
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为研究退火工艺对冷轧中碳钢组织、织构演变以及力学性能的影响,利用OM、SEM、XRD、显微硬度计和万能试验机展开研究。结果表明,500 ℃保温时,以回复软化机制为主,被压扁的铁素体在保温30 min时才出现少许再结晶,保温10 min之后,显微硬度变化不明显,渗碳体以片层状为主;600 ℃保温时,其软化机制以再结晶为主,保温20 min时,仍存在部分未再结晶的变形铁素体晶粒,渗碳体片层以粒状为主,多偏聚于原珠光体区域,显微硬度急剧降低,保温30 min时再结晶完成;700 ℃保温10 min时铁素体再结晶基本完成,渗碳体为均匀的粒状分布,显微硬度变化较小;随退火温度升高以及保温时间的延长,γ织构强度减弱,而(110)<001>织构和γ’织构强度逐渐增强;当退火工艺为700 ℃保温10 min时,可以获得较好的强韧性组合。 相似文献
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对低碳钢进行表面机械研磨处理(SMAT),研究组织变化及其对性能的影响.结果表明:经过SMAT后,低碳钢上形成了厚度约为40 μm的纳米组织表层,在深度为40~80 μm处获得亚微晶组织;表面纳米化不仅提高了低碳钢表面的硬度和耐磨性,而且在不明显降低韧性的前提下提高了板材的整体强度;在纳米到微米量级的范围内,晶粒尺寸与硬度之间满足Hall-Petch关系. 相似文献
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用非晶晶化法制备纳米晶材料 总被引:6,自引:0,他引:6
纳米晶材料具有一般固体材料所没有的优异的力学和电磁特性。通常的纳米晶材料为粉末、薄膜或细丝,因其尺度比较小,产业化比较困难。利用非晶晶化的方法可以制备纳米晶带材、丝材和粉末。例如纳米晶磁性材料Fe-Nb-Cu-Si-B、纳米晶强度材料Al-Ni-B-Fe等已用此法生产。其中纳米晶磁性材料已大量生产,达到实用规模。实验表明,非晶的成分、制备工艺以及随后晶化的方式都影响纳米晶的形成和以后的使用性能。 相似文献
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介绍了高能喷丸表面纳米化技术的设备及机理,并阐述了其对纯钛表层晶粒分布、力学性能及生物活性的影响. 相似文献
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本工作采用光学,电子显徽术(TEM和SEM)及定量金相等技术观测了V和Nb—V微合金化中碳非诚质钢连续冷却后的显微组织,分析了显微组织与力学性能的关系。结果指出:Nb—V复合微合金化不仅更有效地细化钢的组织,而且显著地影响碳化物沉淀的析出方式—抑制其相间析出,因此,可提高钢的强度,并可改善韧性。 相似文献
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《钢铁研究学报(英文版)》2016,(2):145-150
The microstructure and mechanical properties of medium carbon steel after cyclic heat treatment were in-vestigated.The effects of cyclic numbers and long time annealing on the microstructure and mechanical properties of the experimental steel were compared.A short-duration (5 min)holding at 1 023 K (above A1 temperature)and a short-duration (3 min)holding at 893 K are adopted in each cyclic heat treatment.The spheroidization is accelerated during cyclic heat treatment,and the spheroidizing ratio grows with cyclic numbers.After 1 2-cycle heat treatments, there are few incompletely spheroidized regions in the specimens,and cementite lamellae mostly change into cement-ite particles.The morphological character of cementite for 12 cycles is similar to that undergoing annealing for 10 h at 973 K.The strength of the experimental steel after 5-cycle heat treatment is the lowest in the following cyclic heat treatment,but it is still higher than that of specimens with subcritical annealing over a long period (10 h).After 12-cycle heat treatment,the strength of the experimental steel is close to that of the normalized steel,and the plasticity is the best in all heat-treated specimens. 相似文献
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低碳贝氏体钢的组织类型及其对性能的影响 总被引:12,自引:2,他引:12
低碳贝氏体钢受控冷工艺的影响会得到不同类型的组织,在较慢速冷却时,在奥氏体中先形成针状铁素体,残余奥氏体会被包裹在铁素体之中,形成粒状贝氏体团。工业轧制试验表明.不同控制冷却工艺可得到两类组织,一类出现黑珠组织(富碳马氏体组织).具有该组织的钢轧态冲击韧性低。另外一类为细化的板条贝氏体组织,具有该组织的钢轧态强度高,冲击韧性好,但伸长率不足。通过回火处理,存在黑珠组织钢的冲击韧性能得到提高,超细化板条贝氏体组织钢的伸长率也能得到改善,但后者屈服强度会比前者高100MPa左右。 相似文献
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超高碳钢的回火组织及力学性能 总被引:5,自引:0,他引:5
用CM200型透射电子显微镜研究了超高碳钢双相区淬火 中、高温回火后的组织,用Instron型拉伸试验机测定了力学性能.结果表明:650℃的回火组织为等轴状的铁素体与球状的渗碳体,屈服强度σ0.2=1127MPa,抗拉强度σb=1 266 MPa,均匀伸长率δu=8.26%,总伸长率δt=9.71%,维氏硬度HV为397;450℃回火组织的铁素体保持淬火的形态,回火碳化物为ε碳化物在基体上以断续的片状析出,σ0.2=1 911 MPa,σb=2 028MPa,δu=δt=1.88%,HV为595;400℃回火组织中的铁素体保持淬火的形态,回火碳化物在位错处几乎呈网状析出,拉伸无塑性,HV为703. 相似文献
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Liningplateisoneofthemostimportantwear resistantcomponentsofballmills .Itmustmeetvar iousrequirementsforthemachinesaccordingtoop eratingconditions .Recently ,aseriesofwear resis tantmaterialshasbeendevelopedfordifferentballmillsinChina ,e .g .high carbonmediu… 相似文献
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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 608 to HRC 616 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 592 to HRC 616 and the Charpy U-notch impact toughness will retain about 173 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. 相似文献
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稀土-低熔点合金复合变质处理对超高碳钢微观组织及力学性能的影响 总被引:1,自引:1,他引:0
采用自制的稀土-低熔点合金对一种含碳量为1.9%的超高碳钢进行了变质处理,通过OM,SEM,EDS,DSC研究了变质处理和热处理工艺对超高碳钢的微观组织和力学性能的影响.结果表明:超高碳钢经变质处理后,共晶碳化物断网,获得了不连续的块状碳化物,初生奥氏体晶粒明显细化;由于Ce2O2S的吉布斯自由能负值较大,其稳定性较高,因此,稀土元素与O,S在钢中最易形成的稀土氧硫化合物为Ce2O2S;同时稀土与低熔点合金元素的加入,是强烈促进珠光体的元素,具有稳定珠光体的作用,提高了奥氏体化温度;经淬火与低温回火后,获得了马氏体基体上分布着弥散均匀、细小的不连续断网碳化物,冲击韧性得到了明显提高,其ak值由5.8 J·cm-2增加到12.5 J·cm-2,且硬度值基本保持HRC=65,获得了良好的综合力学性能. 相似文献