共查询到20条相似文献,搜索用时 200 毫秒
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采用脉冲激光和光纤激光分别对碳钢进行激光焊接工艺研究。通过优化焊接工艺参量, 均可以得到较好的焊接焊缝, 而且焊缝的显微硬度均大于母材。对两种不同类型激光焊接的焊缝形貌、微观组织、显微硬度进行对比分析, 发现光纤激光焊接的外观更平整, 焊缝质量更好, 焊缝组织的显微硬度提高了43%。 相似文献
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利用6 kW光纤激光器的激光沉积修复系统和电磁感应加热设备,采用TA15钛合金粉末在基板未预热和预热到200℃、400℃时分别进行激光沉积修复实验。利用光学显微镜、显微硬度计、压痕法应力测试仪对激光沉积修复试样的显微组织、显微硬度、残余应力进行测试分析,得到不同预热温度对激光沉积修复显微组织、显微硬度、残余应力的影响规律。结果表明:随着感应预热温度的升高,片层组织变得粗大,初生相生长更加充分;组织分布均匀化,显微硬度轻微降低;残余应力明显减小。为感应加热辅助激光沉积修复提供指导依据。 相似文献
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采用光纤激光器对300M超高强度钢进行激光表面重熔处理,分析了不同激光功率和扫描速率下重熔表面的显微组织、硬度以及电化学腐蚀行为。结果表明:表面重熔区域的显微组织主要由马氏体以及残余奥氏体组成;扫描速率越大,显微硬度越高,显微硬度的均值约为704HV;激光重熔后,材料表面的自腐蚀电位正移,腐蚀电流密度下降;在激光功率为300W和扫描速率为33mm/s条件下得到的重熔层的耐蚀性最好。 相似文献
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激光重熔对TC4钛合金表面激光原位熔覆层微观组织与性能的影响 总被引:1,自引:1,他引:0
为了进一步提高激光原位熔覆层的质量,利用激光重熔方法对TC4钛合金表面激光原位熔覆层进行了处理。采用扫描电镜(SEM)、X射线衍射仪(XRD)和显微硬度计分别对比研究了熔层的显微组织、相分布和显微硬度。结果表明,适当工艺参数的激光重熔处理可以消除位于原位熔覆层底部的大气孔,可以使熔层中的陶瓷相分布更均匀,从而提高熔层的组织致密性;激光重熔处理后熔层硬度值的梯度变化减弱,熔层的平均显微硬度与质量的稳定性均得到提高。 相似文献
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应用5kW横流CO2激光器对核阀阀瓣密封面进行Co基合金的激光熔覆处理,用金相显微镜、扫描电镜、能谱分析仪等分析手段对涂层的组织、晶粒度、显微硬度和稀释率进行了分析.结果表明:激光熔覆层的显微组织、晶粒度、熔层稀释率、热影响区宽度、显微硬度等均显著优于等离子喷焊和堆焊工艺. 相似文献
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激光熔覆硬质合金WC-TiN-Co特性的研究 总被引:3,自引:1,他引:2
本文介绍大功率CO2激光束在45钢表面涂敷WC-TiN-Co,进行了激光熔覆处理,对处理后样品的显微组织、物相、硬度分布和耐磨性能进行了测试和分析,结果表明:45钢表面的化学成分和显微组织发生了根本性的变化,硬度和耐磨性得到了很大提高。 相似文献
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References: 《光机电信息》2007,24(5):41-43
Though the laser trimming resistance has been an old laser machining industry for over 30 years, the development of technology brings new alternative lasers which can be used for the traditional machining. The paper describes application of various lasers to laser trimming resistance system including early traditional krypton arc lamp pumped Nd:YAG to laser, modern popular diode pumped solid state laser and the present advanced harmonic diode pumped solid state laser. Using the new alternative lasers in the laser trimming resistance system can dramatically improve the yields and equipment performance. 相似文献
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An experimental way to analyze the thermal characterization of semiconductor lasers based on spectroscopy method under pulse driving conditions has been developed. By using this way the thermal characteristics of strain compensated 1.3μm InAsP/InGaAsP ridge waveguide MQW laser diodes have been investigated. Results show that by measuring and analyzing the lasing spectra under appropriate driving parameters and temperature ranges, the thermal resistance of the laser diodes could be deduced easily. A higher thermal resistance of 640K/W has been measured on a narrow ridge laser chip without soldering. Other thermal and spectral properties of the lasers have also been measured and discussed. 相似文献
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An experimental way to analyze the thermal characteriztion of semiconductor lasers based on spectroscopy method under pulse driving conditions has been developed,By using this way the thermal characteristicss of strain compensated 1.3 μm InAsP/InGaAsP ridge waveguide MQW laser diodes have been investigated.Results shovw that by measuring and analyzing the lasing spectra under appropriate driving parameters and temperature ranges,the thermal resistance of the laser diodes could be deduced easily,A higer thermal resistance of 640 K/W has been measured on a narrow ridge laser chip without soldering.Other thermal and spectral properties of the laser have also been measured and discussed. 相似文献
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应用2kWCO2激光器在45#钢上进行Ni基WC合金的熔敷处理。试验结果表明,激光熔敷层具有较高的硬度和良好的耐磨抗蚀性能。并对合金中WC含量变化对激光熔敷层耐磨损性能的影响进行了研究。 相似文献
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A monolithically integrated laser driver circuit has been fabricated incorporating an InGaAs-transferred electron device (TED) and an InGaAsP mushroom stripe laser emitting at 1.3-μm wavelength. The TED provides a large-signal modulation of the laser diode along with a pulse shaping of the optical output signal. A threshold current of 18 mA of the integrated laser has been obtained. The modulation of the optical output signal by the TED has been demonstrated. For practical application of the circuit under dc-bias conditions the thermal resistance of the TED's has been calculated and an optimum device structure is proposed. The possibility of triggering the circuit optically will be discussed 相似文献
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激光淬火对钛合金微动磨损性能影响的研究 总被引:2,自引:0,他引:2
研究了激光淬火对钛合金微动磨损性能的影响。结果表明:钛合金激光淬火后抗微动磨损能力有所提高,其提高幅度与微动幅度的大小和法向载荷的高低有关,在较大微动幅度或较高法向载荷的条件下,激光淬火可显著地提高钛合金抗微动磨损能力。 相似文献
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In this paper, we propose a new method to evaluate the thermal resistance of laser diodes and light emitting diodes based on the analysis of common emitter characteristics (emission spectrum, power-current and voltage-current characteristics) measured in CW condition. This method has been used to assess the thermal resistance of commercial GaAlAs laser and light emitting diodes emitting at 780 nm and 872 nm respectively. Finally, the method is compared with classic threshold current method carried out on the laser diodes. 相似文献