1）、离心铸造技术是在液态下使双层材料溶合成型，实现了界面的无间隙、连接成分平滑过渡，为实现层界面低应力的全冶金结合创造了条件；
1) the centrifugal casting technology is to make the double-layer material melt and form in liquid state, to realize the seamless interface and smooth transition of connecting components, and to create conditions for the full metallurgical combination of low stress layer interface;
2）、热挤压（或纵轧）加工技术既促进了冶金结合，又改善了双金属复合管综合性能；
2) hot extrusion (or longitudinal rolling) processing technology not only promotes metallurgical combination, but also improves the comprehensive performance of bimetal composite pipe;
3）、热挤压是在三向压应力条件下的金属塑性变形，是常规轧制难生产的镍基合金首选的生产方式；
3) hot extrusion is the plastic deformation of metal under the condition of three-dimensional compressive stress, and it is the preferred production mode of nickel base alloy which is difficult to be produced by conventional rolling;
4）、挤压产品金属致密度高，显微缺陷大大减轻，产品有较高冲击性能。同时，热挤压过程促进了扩散结合机制的作用。
4) the extruded products have high metal density, greatly reduced micro defects and high impact performance. At the same time, hot extrusion promotes the diffusion bonding mechanism.