金相分析技术是目前应用最为广泛的金属材料分析技术之一，可以分为宏观金相分析技术和微观金相分析技术。首先介绍了宏观金相分析技术，并举例介绍了其在失效分析中的应用。然后详细介绍了微观金相分析技术，包括微观金相分析所使用的光学金相显微镜组成、金相试样制备的详细过程及注意事项、以及金相试样的侵蚀方法等。最后，通过大量的、具有代表性的典型实例重点介绍了两种显微金相分析技术，即光学显微技术和电子显微技术在失效分析中的应用。实践证明：金相分析技术经常会以其丰富的内涵和外延揭示出构件失效现象的本质，在机械装备的失效分析中具有非常重要的作用。

Metallographic analysis technique is one of the most widely used metallic materials analysis techniques, and it can be divided into macro metallographic analysis technique and micro metallographic analysis technique. Firstly, the macro metallographic analysis technique was introduced and its application in failure analysis was exemplified. Then, the micro metallographic analysis technique was introduced in detail from the aspects of compositions of optical metallographic microscope, detailed process and matters needing attention of metallographic sample preparation, as well as erosion method of metallographic samples. Finally, through a large number of representative typical examples, the application of two kinds of micro metallographic analysis techniques, namely optical microscope technique and electron microscope technique, in failure analysis was introduced. The practice has proved that metallographic analysis technique often reveals the essence of component failure phenomenon with its rich connotation and extension, and plays a very important role in the failure analysis of mechanical equipments.