浇注法制备表面复合材料用复合剂的强度表征及测试

用改进后的强度测试仪，检测分析了三种自制复合剂不同温度下的抗弯强度，探讨了复合剂强度的测试方法，结果表明：抗弯强度可用来表征用于浇注法制备金属基复合材料的复合剂强度，抗弯强度越高，铸件浇铸成型率越高。     

PLC在接触器试验中的应用

本文介绍了对交流接触器按照UL认证标准,采用PLC进行过载耐久试验,提高了试验的可靠性和试验的自动化程度。     

Ultrasonic technique for measuring porosity of plasma-sprayed alumina coatings

Porosity is an important factor in plasma-sprayed coatings, especially ceramic coatings. Excessive poros-ity can adversely affect the performance of the coated component in various ways. An ultrasonic nonde-structive measurement technique has been developed to measure porosity in plasma-sprayed alumina coatings. The technique is generic and can be extended to other ceramic coating systems. To test the tech-nique, freestanding alumina coatings with varying levels of porosity were fabricated via plasma spray. Samples with varying porosity, obtained through innovative fabrication techniques, were used to gener-ate a calibration curve. The ultrasonic velocity in the low-frequency range was found to be dependent on the density of freestanding coatings (measured via Archimedian techniques). This dependence is the basis of the development of a technique to measure the density of coatings.     

脉冲涡流和电磁声换能器双探头无损检测

在许多情况下，只应用一种NDT技术存在不足，这就迫使NDT操作人员使用一种以上的技术以保证检测出危害被检物使用寿命或功能的缺陷。但分别实施多种技术的检测，就会延长检验时间。介绍了一种新的NDT设施，采用两种不同的非接触无损检测技术进行互补，即电磁声换能器（EMAT）和脉冲涡流（PEC）探头。检测结果表明，脉冲涡流和电磁声换能器因是非接触，所以可应用于材料生产过程中的自动在线检验，也可用于在役检验。     

超声相控阵检测技术及其应用

简述超声相控阵检测技术的发展、原理、特点及相控阵换能器的分类。介绍国外超声相控阵检测成像技术在焊缝和火车轮轴检测方面的应用。超声相控阵检测技术较常规超声波检测具有高速、高效、适合复杂结构件以及能实时成像等优点，在压力容器、核电站和海洋平台结构等工业无损检测领域具有良好的应用前景。     

Evaluation of TiAI and 40Cr diffusion bonding quality using ultrasonic reflection spectrum

Combined with ultrasonic pulse-echo technique, reflection spectrum analysis was introduced to evaluate TiAl and 40Cr diffusion bonding quality. Frequency dependence of reflection coefficient was used to distinguish perfect bonding from imperfect bonding. It is found that the reflection coefficient from perfect bonding interface does not vary with frequency. When the size of imperfections is much smaller than the wavelength of ultrasound, the reflection coeffwient depends on frequency. When the size of imperfections is the same order of or even larger than the wavelength of ultrasound, the reflection coeffwient does not exhibit frequency dependence. However the amplitude of imperfect interface is higher than the amplitude of perfect bonding interface. A combination of reflection spectrum analysis and ultrasonic pulse-echo technique provides more accurate information about the bonding quality of dissimilar materials.     

螺栓轴向应力超声测量技术

简要介绍螺栓轴向应力超声测量的基本原理和测量方法，推导了螺栓伸长量和轴向应力的计算公式，介绍了测试过程中探头的选择、表面状态要求、温度补偿以及测量的适用条件。实际应用表明，该方法容易实施，测量精确度较高。     

合成绝缘子内部缺陷的超声检测

针对合成绝缘子挂网运行后出现的界面击穿、芯棒脆断问题，研究了组成合成绝缘子各材料的声学特点及用超声波进行检测的可行性，采用的方法可实现对界面φ0.5mm圆孔气隙的检测；还研究芯棒机械强度下降与其声速变化的关系，得出了超声可以应用到实际的绝缘子检测工作中的结论。     

模态声发射——声发射信号处理的得力工具

模态声发射是声发射信号处理技术的得力工具。介绍它在声发射源定位、复合材料损伤源识别、疲劳裂纹萌生和扩展的声发射监测以及日历损伤声发射评价等工程实践中的应用。     

THERMOGRAPHIC ASPECT ON LOADING A THIN-WALL PRESSURE VESSEL STEEL

The infrared emission of a high pressure vessel steel and two thin wall pressure vessel modelshave been investigated by use of vibro-thermography.The experimental infrared cracklengths were found to be agreed closely with the optical values during fatigue process.A possi-ble nondestructive testing method used to evaluate the pressure vessel has been given.