爆炸焊接00Cr18Ni5Mo3Si2/16Mn接合界面的TEM观察 (1)

爆炸焊接00Cr18Ni5Mo3Si2/16Mn接合界面的TEM观察

卫英慧胡兰青王云宁许并社黄源

摘要：用透射电镜研究了爆炸焊接复合板00Cr18Ni5Mo3Si2/16Mn的结合界面。结果表明：爆炸焊接复合板的宏观界面为锯齿形；齿间的基板和覆板受强大爆炸冲击力的作用形成几微米宽的过渡区，该区内位错密度增大，并有细小的覆板碎屑存在。齿部边缘的晶粒破碎，齿尖部位有熔化现象，这主要是基于3个方面的原因：一是齿尖处有毛细管状沟槽组织存在；二是齿尖周围有析出物出现；三是齿尖与覆板的铬含量有一定差异。
关键词：爆炸焊接，透射电子显微术，界面，相变
中图分类号：TG142，TG456

A TEM Investigation on Junction Boundary of 00Cr18Ni5Mo3Si2/16Mn Combined Steel Plate Produced by Explosive Welding

Wei YinghuiHu LanqingWang YunningXu BingsheHuang Yuan
Taiyuan University of TechnologyTaiyuan030024

ABSTRACT：Junction boundary of 00Cr18Ni5Mo3Si2/16Mn combined steel plates produced by explosive welding technology was investigated by means of TEM. It was concluded that the junction macro-boundary is of sawtooth shape and there is a transition region, several micrometers in width, between the sawteeth where dislocation density is high and some fine fragments of coating plate exist. Grains of the sawtooth edge are broken and the sawtooth tips are melted because: (1) there is a capillary-shaped notch structure at the sawtooth tip; (2) some precipitates ocurr around the sawtooth tips; (3)there is a difference in chromium content between the sawtooth tip and the coating plate.
KEY WORDS：explosive welding,TEM,boundary,phase transformation

爆炸焊接是生产复合板的一种非常有效的方法，它能将某种具有特殊性能、价格昂贵的覆板通过爆炸提供的能量与普通的基板相结合，形成综合性能优良的复合板，可用于耐蚀、耐高压、耐冲刷等工况条件。我国三峡工程的导流洞就是用这种复合板砌焊而成的。
复合板的性能除与基板和覆板的性能有关外，其结合界面的性能也是非常关键的。因为结合界面性能的好坏，直接影响到覆板的抗拉、抗弯、抗扭转及耐蚀性能。因此了解爆炸后界面的结合方式很重要，但由于制备透射样品较困难，涉及这方面的研究报道很少。作者对爆炸焊接的00Cr18Ni5Mo3Si2/16Mn复合板的结合界面组织进行了TEM观察。

1实验方法
实验用复合板基板为厚20 mm的16Mn钢板，覆板为厚3 mm的00Cr18Ni5Mo3Si2双相不锈钢，通过爆炸焊接使两者结合。覆板与基板的化学成分(质量分数)示于表1。
先用线切割法切取带有结合区的薄片，经过机械抛光、双喷抛光后，在离子减薄设备上减薄，最后制成φ3 mm的透射电镜试样。用带有双倾台的H-800透射电镜观察试样的组织形态及其分析结构。

表1复合板用钢板的化学成分/%
Table 1Chemical composition of the steel plates/%

钢板 C Si Mn P S Cr Ni Mo 00Cr18Ni5Mo3Si2
16Mn 0.027
0.12～0.20 1.62
0.2～0.6 1.25
1.2～1.6 0.028
≤0.05 0.004
≤0.05 19.48
- 5.76
- 2.70
-