共查询到19条相似文献,搜索用时 109 毫秒
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T10钢宽带激光相变硬化的组织与性能研究 总被引:3,自引:0,他引:3
采用宽带激光相变硬化工艺对T10钢表面进行了改性处理 ,并对改性后的组织与性能进行了研究 ,结果表明 ,硬化区组织为针状马氏体 +少量残余奥氏体。热影响区组织为少量针状马氏体 +珠光体 +网状渗碳体。基材组织为珠光体+网状渗碳体。淬硬层表面的洛氏硬度最高值为HRC6 3 5 ,淬硬层内的显微硬度分布均匀 ,最高显微硬度值约为HV94 0 ,从硬化区→热影响区→基材显微硬度呈梯度变化。激光相变硬化后淬硬层表面的残余应力分析表明 ,淬硬层表面存在压应力 ,压应力的最大值为 - 4 2 9MPa。 相似文献
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常用铸铁的深层激光硬化 总被引:2,自引:0,他引:2
研究表明:对常用的灰口铸铁和球墨铸铁表面进行激光熔凝处理,可以获得连续平整、没有气孔裂纹、有效深度为1~1.3 mm 的均匀硬化层。熔化层组织细密强韧,硬度可达HV_(0.1)714—970,具有优良的耐磨性,热硬性和抗擦伤剥落的性能,因而可以适应某些工作的苛刻的服役条件,有广泛的应用前景。 相似文献
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对激光淬火Cr12模具钢进行了相变硬化处理,分析了搭接对硬化层硬度的影响,并进行金相分析及探伤,结果表明:在不同的激光相变硬化工艺下,可得到硬化层深度为0.23~0.43 mm的硬化层;激光淬火得到硬化层硬度由表及里呈现一个逐渐过渡的硬化曲线,硬化层最高685 HV,平均硬度为596 HV。采用由圆弧到上表面的搭接次序及20%的搭接量可满足实际使用要求。硬化层组织为高细化的马氏体。激光淬火处理后无变形、无裂痕,且工艺简单,便于推广。 相似文献
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45#钢激光相变硬化组织及性能 总被引:1,自引:0,他引:1
应用5kW连续CO2激光器对正火态45#钢表面进行激光相变硬化处理,采用金相显微镜和显微硬度计进行显微组织分析及硬度测试。结果表明,激光相变硬化后的剖面组织可分为完全淬硬区(马氏体)、不完全淬硬区(马氏体、铁素体和珠光体)、高温回火区(回火索氏体)。激光相变硬化处理明显提高了正火态45#钢的硬度。当激光功率一定时,随扫描速度的增加,淬硬层深度逐渐降低,且在v=400mm/min和v=1000mm/min时表面硬度分别出现峰值。 相似文献
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采用CO2激光器对HT20-40灰铸铁进行了熔一凝硬化处理,重点探讨了其组织特征及形成机理.结果表明,HT20-40灰铸铁激光硬化带具有三层不同的显微组织:(1)与快速熔凝对应的白口化组织-微细莱氏体;(2)局部熔化区,具有铸态特点的岛状组织和马氏体,石墨部分消失;(3)相变区主要为隐晶马氏体,片状石墨基本保持原状.而且,通过适当的工艺控制,可使局部熔化区消失,仅存在熔-凝区和相变区. 相似文献
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The abrasive wear resistance of white cast iron was studied. The iron was solidified using two solidification rates of 1.5 and 15 °C/s. Mass loss was evaluated with tests of the type pin on abrasive disc using alumina of different sizes. Two matrices were tested: one predominantly austenitic and the other predominantly martensitic, containing M3C carbides. Samples with cooling rate of 15 °C/s showed higher hardness and more refined microstructure compared with those solidified at 1.5 °C/s. During the test, the movement of successive abrasives gave rise to the strain hardening of the austenite phase, leading to the attainment of similar levels of surface hardness, which explains why the wear rate showed no difference compared to the austenite samples with different solidification rates. For the austenitic matrix the wear rate seems to depend on the hardness of the worn surface and not on the hardness of the material without deformation. The austenitic samples showed cracking and fracture of M3C carbides. For the predominantly martensitic matrix, the wear rate was higher at the solidification rate of 1.5 °C/s, for grain size of 66 and 93 μm. Higher abrasive sizes were found to produce greater penetration and strain hardening of austenitic matrices. However, martensitic iron produces more microcutting, increasing the wear rate of the material. The analysis of the worn surface by scanning electron microscopy indicated abrasive wear mechanisms such as: microcutting, microfatigue and microploughing. Yet, for the iron of austenitic matrix, the microploughing mechanism was more severe. 相似文献
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不锈钢复合板的热处理需要综合考虑基材和覆材2种材料的特性,热处理工艺不当会导致基层力学性能恶化或者降低覆层的耐蚀性。14Cr1MoR的热处理工艺为正火+回火,而S31254在〈1 000℃时极易析出碳化物、氮化物和金属间化合物等有害相,这给14Cr1MoR+S31254复合板的热处理增加了难度。通过对不同温度下14Cr1MoR和S31254两种材料显微组织和理化性能变化规律的分析,确定了使用14Cr1MoR+S31254爆炸复合板消除加工硬化、恢复力学性能的热处理方案。 相似文献
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J.T.H. Pearce 《Wear》1983,89(3):333-344
The wear behaviour of an austenitic high chromium cast iron was investigated under conditions of high stress abrasion using a specimen-on-track test apparatus. The austenite matrix at the wear surfaces of test specimens work hardened during abrasion giving hardness values up to 950 HV but the depth of hardening was seen to be much smaller than that obtained under service conditions. The nature of the work hardening was studied by thin foil transmission electron microscopy. This work has provided evidence of strain-induced martensite formation which is believed to be responsible for the observed increases in hardness. 相似文献
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