在铂金材料的焊接过程中，最主要采用的助焊剂是氢化硝。

Chengdu is a famous city with long history. Locating in the southwest of China, it is the capital city of Sichuan Province, it is called “the Land of Abundance”. It is said that Chengdu got its name over 2000 years ago and it had never changed since then. There is a large number of famous cultural sites and delicious snacks there, which have always been attraction to tourists from around the world. Tourists go not only to see the historical sites and to taste the snacks, but also because that it has beautiful scenery. A walk at the sides of the beautiful Jinjiang River will offer a feast for anyone’s eyes. In a word, Chengdu, as a famous saying goes, is a city where you don’t want to leave once you have come.