共查询到19条相似文献,搜索用时 156 毫秒
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电液压脉冲水气射流强化淬火后工具钢的表面研究 总被引:1,自引:0,他引:1
为了提高工具钢表面的精度,提出了采用电液压脉冲水气射流来强化淬火后工具钢表面的新方法.基于电液压脉冲水气射流发生器的工作原理和结构,通过对铁及其合金的电液压脉冲水气射流强化的理论和试验研究结果,结果表明:电液压脉冲水气射流的最大优点是它所产生的压力可任意调节,根据工件的不同要求,完成对零件表面的强化.高速变形对承受脉冲载荷工件的物理力学特性有着重大影响,电液压脉冲水气射流消除铸件和焊接件的残余应力达40%~70%,并且不会影响工件的加工表面质量. 相似文献
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水轮机空化的超声监测技术研究 总被引:14,自引:0,他引:14
简要介绍水轮机空化现象的超声检测原理和方法,给出了一组试验结果,表明超声法优于传统的能量法,超声法中空化噪声强度法优于噪声脉冲计数法。 相似文献
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液压系统压力脉冲模拟器是一个分布参数的复杂非线性系统,要产生符合规范的压力脉冲波形难度很大.针对这一问题,应用AMESim软件建立了液压系统压力脉冲模拟器的仿真模型,进行脉冲波形的仿真计算.分别研究油液体积弹性模量、油液黏度、蓄能器容腔大小和换向阀通流能力等参数对波形的影响.仿真和分析表明:压力脉冲的形成与多种因素有关,在系统设计中必须根据被试件特性和压力波形参数对管路的配置和阀件的动态特性等进行优化设计. 相似文献
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由于边侧稀疏波的作用,爆炸焊接界面边界与中心区域形貌结构存在差异。然而学术上对焊接界面形貌差异分析仍处于定性水平,尚未建立定量分析方法。据此,本文尝试对爆炸焊接界面形貌差异开展定量化评价。研究过程中首先建立冲击波作用下金属复板弹粘塑性模型以分析波状界面的形成,并开展2024Al对称爆炸焊接;随后运用三维超景深显微镜获得界面形貌图像,结合冲量理论,定义中心区域与边侧区域分界线;最后基于分形理论计算图像轮廓分维与多重分维谱。由分维与多重分形谱数据可定量表征界面的起伏程度与表面最大、最小概率分布,从而实现焊接界面形貌差异定量描述。 相似文献
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本文主要论述点焊机焊接电流信号检测电路的设计、分析和测试。被检测的焊接电流信号是频率为50Hz.不连续的非正弦波。该线路测试结果:当点焊机的焊接电流为2.66~15KA时.电路输出正脉冲.且每次焊接时输出正脉冲的前沿比焊接电流出现时间延时不大于10ms,脉冲的后沿比焊接电流消失时间延时小于10ms。本线路已用在DN6-26型机器人点焊系统中。 相似文献
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Rapid and economical evaluation of concrete tunnel linings with impulse response and impulse radar non-destructive methods 总被引:1,自引:0,他引:1
Concrete tunnel linings, whether pre-cast or cast in place, are designed to distribute external soil pressures as uniformly as possible through the tunnel shell. To this effect, the contact between the lining and the surrounding soil is usually assured by grouting the annular space between. Any voiding in the grout at this interface negates the purpose of the grout. This paper describes the use of non-destructive testing to examine the efficiency of tunnel lining grouting programmes, with particular emphasis on results obtained by the impulse response and impulse radar methods. The rail, water supply and sewer tunnels discussed in this article vary in diameter between 1 and 5 m, and emphasis is placed on the rapid results obtained by these methods. 相似文献
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This paper describes two methods for calibration of the frequency response of transducers used in acoustic emission testing of concrete. The first uses two transducers to be calibrated coupled back-to-back. One of the transducers is excited by an input signal. The frequency response of the transducers is then deduced from analysis of the output signal. Two types of excitation may be used: sinusoidal excitation, which makes it possible to obtain the response point by point, and impulse excitation, which gives the frequency response directly. The second method uses the breaking of a pencil lead on the transducer face. The response obtained must then be corrected. Three types of transducers, used in specific applications for acoustic emission testing of concrete, are then characterized by these methods. 相似文献