阀芯端帽工作面激光合金化扫描路径规划

基于阀芯端帽的外形特征及磨损状况,规划阀芯端帽工作面激光合金化的扫描路径.设计双向变螺距螺旋式扫描路径对阀芯端帽工作面进行激光合金化,推导出该扫描路径的参数方程及螺旋角计算公式,使用Nd:YAG激光器进行编程加工,将采用双向变螺距螺旋式扫描路径的试件与采用直纹式扫描路径的试件分别进行磨损试验.研究发现:采用双向变螺距螺旋式扫描路径时,阀芯端帽工作面的耐磨性能是直纹式扫描路径的1.8倍,而热变形量约为直纹式扫描路径的1/3.     

阀芯端帽工作面激光合金化夹具设计

设计夹具解决阀芯端帽工作面激光合金化时,采用直接装夹方式易产生装夹变形及定位精度低等问题,同时可提高阀芯端帽合金化加工效率。     

激光合金化冷轧辊的技术研究

激光表面合金化是一种局部改性处理方法，可以改变基体表面的化学成分，从而提高金属的强度、耐磨性、耐蚀性、高温抗氧化性等。将这种技术应用于冷轧辊的表面处理，不仅可以改善轧辊表面的性能，减少轧辊在使用中的重淬次数，而且，还可以制作不同表面形貌的轧辊，以满足生产的需要。探讨了冷轧辊表面激光合金化技术的应用工艺，并对试样进行硬度分析和金相分析的研究，显示了激光合金化技术对材料表面性能的改进。     

激光表面合金化裂纹的研究

对铸铁进行了大量的激光表面合金化试验研究 ,找出了工艺参数、基材类型、试样的几何尺寸和合金粉末种类对激光表面合金化裂纹率的影响规律     

45钢激光表面合金化层性能研究

探讨了４５钢上Ｆｅ基、Ｓｔｅｌｌｉｔｅ１２激光表面合金化层的组织和性能,分析了合金层与基体之间的显微组织、成分分布,测试了合金层的显微硬度、耐磨性和耐蚀性。试验结果表明,激光表面合金化是提高材料表面性能的一种有效方法。     

激光表面合金化裂纹的研究

对铸铁进行了大量的激光表面合金化试验研究,找出了工艺参数、基材类型、试样的几何尺寸和合金粉末种类对激光表面合金化裂纹率的影响规律。     

工艺参数对激光合金化层裂纹的影响

主要介绍了在30CrMnSi表面进行Ni-25粉末的激光合金化试验。在保持频率和脉宽不变的情况下,通过改变激光的电流大小和扫描速度,进行不同工艺条件下的单道合金化试验。试验表明,激光工艺对合金化层裂纹敏感性有明显影响。通过分析得出,当激光电流为170A,扫描速度为1.3mm/s时,能够得到较好的合金化层,合金化层没有裂纹。     

高速钢刀具表面激光合金化

本文记述了使用CO_2激光器,对预敷有WC或TiC粉末的高速钢刀具表面进行激光表面合金化处理的实验,通过测试和分析,高速钢刀具表面经激光合金化处理后,其硬度和耐磨性能有很大提高。     

浅析激光表面合金化技术的应用及发展方向

介绍激光表面合金化技术的原理、特点和应用,对激光表面合金化技术的国内外研究进展进行综述,指出该技术存在的问题,并对其发展方向进行了预测和展望。     

The effect of oxide-forming alloying elements on the high temperature wear of a hot work steel

A great deal of research has been conducted to clarify the role of oxide films in the wear of metals. Oxides formed during dry sliding of steels at high temperatures determine their tribological behavior. The present work deals with the influence of the oxide-forming alloying elements aluminum and silicon on the oxidation and wear of three selected hot work steels. For this investigation, ball-on-disc experiments were carried out in ambient air and 500 °C. Wear tracks on the disks and balls were characterized using both a scanning electron microscope and an optical profiler. The oxidation products were characterized using X-ray photoelectron spectroscopy and energy-dispersive electron probe microanalysis. The results show that the alloying elements aluminum and silicon yield a reduction of the oxide film thickness and thus lead to an increase in mechanical wear as temperature rises.     

An investigation of the surface contours in laser grooving

The surface contours generated in laser grooving by a compound jet nozzle on mild steels have been characterized experimentally and theoretically in this study. A side-jet grooving nozzle was designed with various attacking angles to achieve the optimum conditions on the material removal rate and surface roughness for this technique. The grooving depth was estimated through the formulation of the energy equations with the consideration of exothermic heat and the grooving contours were measured by the laser displacement sensor. The results show a close agreement between the theoretical prediction and experimental testing. The process characteristics and the parametric analysis were also discussed.     

矫直辊表面激光强化实验研究

采用不同激光工艺参数对9SiCr钢矫直辊表面进行强化处理,探讨各加工参数对硬化层深度和硬度的影响。     

Zr-4合金激光表面Nb合金化层厚度与组织研究

研究了预涂铌的Zr-4合金经激光表面合金化（LSA）后的合金化层厚度、组织、和显微硬度，并分析了产生变化的机理。由于激光参数不同，合金化后含铌层的厚度在210～360μm之间，合金化层距表面100gm深度处铌含量在1．84～2．67wt％之间。合金化层组织为树枝晶，随着冷却速度的增加，枝晶间距变小；合金化层的显微硬度随冷却速度的增加而增加，最大达到了430HV。     

Preparation and Tribological Properties of NiCrBSiC Reinforced Laser Alloying Layer

This work is based on dry sliding wear of an NiCrBSiC-reinforced layer deposited on Ti-3Al-2V alloy using the laser alloying technique, the parameters of which could provide almost crack-free layers with minimum dilution and very low porosity. Scanning electron microscopy (SEM) images indicated that a laser alloying layer with a metallurgical joint to the substrate was formed. Compared to Ti-3Al-2V substrate, an improvement in wear resistance was observed for the alloying layer. In addition, the friction and wear behavior of the laser alloying layer was highly dependent on the applied normal load and sliding speed.     

High-precision detection of focal position on a curved surface for laser processing

A new technique for detecting the focal position of a curved surface provides several advantages both in research and industrial applications. The quality of patterns lasered on a roll surface is determined by the precision of the focus detection, and surfaces of the massive rolls used in laser fabrication can be difficult to adjust properly using conventional technologies. Here, a unique method for detecting the focal position of a curved surface based on the reflected profile of a laser beam is presented. The versatility of the proposed technique results from being able to adjust the laser beam based on changes in the shape and diameter of the beam spot when the specimen surface deviates from the focal plane. A theoretical model based on three-axis movement is proposed, and experimental setups are developed based on the model. Analysis of the obtained results enables high precision positioning of the specimen and identification of the focal point. Furthermore, the presented technique can be used to locate the focal point on any curved surface. Therefore, the theoretical model, analysis results, and focal detection method can be combined in an algorithm for a novel auto-focusing system that can be applied to laser processing of curved surfaces, such as fabricating microgrooves, or engraving roll surfaces in printed electronics.