W6Mo5Cr4V2高速钢激光相变硬化组织与耐磨性

研究了Ｗ６Ｍｏ５Ｃｒ４Ｖ２（Ｍ２）高速钢经激光相变硬化后的组织与耐磨性。结果表明,经激光淬火后可获得１０００ＨＶ以上的超高硬度,组织是细马氏体,激光相变硬化层的耐磨性与常规处理的相比提高约４０％     

激光热处理新技术及其应用

激光热处理新技术及其应用中国科学院力学研究所材料加工特种工艺工程研究中心（北京１０００８４）陈光南ＮｅｗＴｅｃｈｎｏｌｏｇｙａｎｄＡｐｐｌｉｃａｔｉｏｎｏｆＬａｓｅｒＨｅａｔＴｒｅａｔｍｅｎｔＣｈｅｎＧｕａｎｇｎａｎ（Ｌａｂ．ｆｏｒＭｅｃｈａｎｉｃｓ...     

激光表面改性对轧辊用高速钢组织与硬度的影响

用横流激光器对高速钢轧辊材料进行了激光重熔和激光相变硬化表面处理,利用金相显微镜对激光重熔层与硬化层的形貌进行了研究,用带能谱的扫描电镜与X射线衍射仪（XRD）对微区成分以及相结构进行了分析,用硬度计测量了试样表面硬度.结果表明,高速钢轧辊材料经激光重熔处理后,表面硬度明显降低,碳化物呈网状分布;经激光相变硬化后的试样表面硬度显著提高,最高值达到68.5HRC,碳化物呈球状孤立分布.     

45钢激光相变硬化组织及性能研究

    利用轴流CO₂激光加工机对45钢在轴流基模条件下进行激光相变硬化处理，并研究了其激光相变硬化组织及性能.结果表明，改性层微观组织由表层至基体依次为：表面熔凝区为片状马氏体，均匀相变硬化区为隐晶马氏体，过渡区为混合马氏体、屈氏体和部分未熔的铁素体；激光相变硬化改性层的硬度与基体相比有大幅度提高；最高硬度（约为基体的3倍）出现在次表层；激光相变硬化处理后耐蚀性有所提高，随扫描速度增加，耐蚀性增强.     

金属材料的激光相变硬化机理及其工艺参数优化

简要介绍了激光表面技术中的激光相变硬化，阐述了金属材料的激光相变硬化机理，分析了激光功率、扫描速度和光斑直径等工艺参数对硬化效果的影响，指出用激光能量密度描述激光加工工艺参数之间的耦合作用对硬化效果的影响规律。     

激光表面处理对Zr—4合金板材疖状腐蚀的影响

研究了几种激光表面处理工艺对不同状态的Ｚｒ－４合金板材泡疖腐蚀的影响。实验结果表明：激光表面处理可以显著提高Ｚｒ－４合金抗疖状腐蚀性能；激光表面处理前Ｚｒ－４合金板材的状态（消除应力退火态、再结晶退火态、冷加工态）对激光表面处理后板材的疖状腐蚀性能的影响不明显     

激光表面处理对Zr－4合金板材疖状腐蚀的影响

研究了几种激光表面处理工艺对不同状态的Ｚｒ－４合金板材泡疖腐蚀的影响。实验结果表明：激光表面处理可以显著提高Ｚｒ－４合金抗疖状腐蚀性能；激光表面处理前Ｚｒ－４合金板材的状态（消除应力退火态、再结晶退火态、冷加工态）对激光表面处理后板材的疖状腐蚀性能的影响不明显     

W18Cr4V高速钢激光相变硬化层中碳化物的溶解及碳的扩散

研究了Ｗ１８Ｃｒ４Ｖ高速钢激光相变硬化组织中碳化物的形状，大小和分布、碳的扩散及碳化物的溶解机制。试验结果表明，激光超快速加的相变过程中仍存在碳的扩散，扩散距离约为数百ｎｍ，碳化物的溶解主要是通过尖角－均匀溶解机制进行的，另外还存在断理解溶解机制。     

中碳调质钢激光热处理耐蚀性研究

采用5 kW横流CO_2激光器对40Cr钢表面进行大面积的激光相变硬化;用失重法和电化学方法测试材料激光相变硬化后的耐蚀性.结果表明,在搭接率为20%的条件下,调质态的40Cr激光相变硬化后腐蚀电流密度为110.4μA,耐蚀性较母材提高了30%,而正火态的40Cr激光相变硬化后腐蚀电流密度为293.9 μA,耐蚀性能大幅度下降.     

激光表面改性主要技术

<正>(1)激光相变硬化:功率密度可达106W/cm2以上,能在0.001～0.01 s时间内使工件加热到1 000℃以上,冷却速度可达104℃/s,硬化层深度0.1～2.5 mm。(2)激光表面熔化处理:激光表面合金化、激光表面熔覆、激光表面重熔、激光表面复合改性、激光上釉(功率密度107～108W/cm2)。(3)激光冲击硬化。     

CALCULATION OF 3-D TRANSIENT TEMPERATURE FIELD DURING LASER TRANSFORMATION HARDENING PROCESS

1.IntroductionLasertransformationhardeningprocessisathreedimensiontransientheattransferproblemwhichinvolvesinphajsetransformation,heatconduction,heatconvectionandheatradiation.Thecalculationoftemperaturefieldoflasertransformationhardeningprocessisaprerequisitetotheoptimizationofparametersoflasertransformationhardening.Thisworkstartedintheearlyof1970',uptonow,alotofmodelsandcalculationmethodswereproposedtocalculatethetemperaturefieldoflasertransformationhardeningprocessll--gi.Allthesemodelsareb…     

气缸套激光热处理实验研究

采用YAG固体激光对发动机气缸套进行热处理,研究了离焦量、激光功率、扫描速度及表面处理对激光淬火硬度、淬硬深度及宽度的影响。试图找出激光热处理的最佳参数,供实际工作中参考。     

药物冲头的激光表面强化分析

对药物冲头激光表面淬火后的表面强化层进行了分析研究，并将其与传统的药物冲头热处理进行了在线生产对比，结果表明，表面激光淬火时，当表层区所需能量为30J/mm^2时，便度值最高，表层组织为细小，隐晶马氏体和弥散分布大小不一的合金碳化物，硬度很高，过渡区由于托氏体的析出，硬度明显下降，这种显微组织使冲头耐磨性、抗冲击性都提高，也延长了其使用寿命。     

Laser surface hardening ofAISI H13 tool steel

An attempt was made to improve the surface hardness and wear properties of AISI H13 tool steel through solid solution hardening and refinement of microstructures using a 200 W fiber laser as a heat generating source. The hardness of laser melted zone was investigated. In order to identify the effect of heat input on the laser melting zone, scanning conditions were controlled. The results show that, the hardness of as-received AISI H13 tool steel is approximately Hv 240, and the hardness after laser surface heat treatment is around Hv 480–510. The hardening depth and width are increased with the increase in the heat input applied. Application of experimental results will be considered in tooling industry.     

激光表面淬火强化技术的工艺基础

通过对激光与金属材料表面的交互作用规律的研究,从传热学角度得出了激光固态加热的两个基本规律,从物理冶金学角度讨论了激光快速加热作用条件下的金属晶体的缺陷特征、残余奥氏体特征、淬火马氏体特征、组织遗传性以及其各自的形成原因。     

Characterization of laser treated steels using instrumented indentation by cylindrical flat punch

The aim of the present work is to assess the possibility of predicting the thickness of the hardened layers produced by High Power Diode Laser (HPDL) heat treatment. Instrumented indentation by cylindrical flat punch was carried out in order to evaluate the effectiveness of the surface-hardening heat treatments on milled AISI 1040 steel substrates by varying laser operational parameters as well as the morphology of steel substrates. In particular, the trend in load-penetration depth were obtained, supporting the identification of the depth at which the hardened layer starts transferring the deformation to the softer substrate, that is, the Critical Transition Depth (CTD) in addition to identifying the overall degree of hardening reached by the laser treated material. On the other hand, hardness profiles and the thickness of hardened layers were also monitored by using combination of Vickers micro-hardness tests and standard metallographic characterizations.Analytical examinations and simple mathematical simulations of the experimental results coming from indentation tests and conventional testing procedures showed good correlation between the extent of the heat affected zone (HAZ), hardness and CTD. In conclusion, this study demonstrates that indentation tests are an effective, sensitive, fast, and low-cost characterization technique for heat treated steels.     

片状珠光体碳钢的激光相变硬化区的理论预测及验证

片状珠光体碳钢的激光相变硬化区的理论预测及验证朱心昆，孙加林，王剑华（昆明工学院）１引言应用激光对金属表面相变硬化处理时，最令人关心的是区化区的形状和尺寸，倘若能根据工艺参数和材料的原始组织等已知条件，将激光作用区的温度场与材料的组织形态和相变规律结...     

Influence of laser hardening and resulting microstructure on fatigue properties of carbon steels

Cylindrical specimens of a CSN 12050 carbon steel, equivalent to the UNS G 10420 steel, with two different initial microstructures, normalized and heat treated, were surface processed without melting by a 2.5 kW, CO₂ laser to study the effects of laserbeam hardening and resulting microstructure on fatigue properties and mechanisms. Two configurations of circumferential laser passes were made, resulting in one and three separate surface hardened lines, respectively. Fatigue resistance was studied using alternating bend tests. A detailed metallographic study and x-ray measurements of surface stresses were carried out. It was shown that the laser beam hardening under different conditions either reduced or slightly improved the fatigue life.     

激光相变硬化技术的研究现状及进展

主要介绍了激光相变硬化的特点及强化机理、激光表面相变硬化工艺。分析了钢铁材料激光相变硬化后的组织与性能,及近年来激光相变硬化技术在材料科学领域的研究状况。