Recently, the remelting Centre of Xingtai Steel producted grade 15-5PH precipitation-hardening stainless steel successfully to further expanding new sales market and promoting transformation and upgrade of products.

　　Grade 15-5PH is a kind of martensite precipitation-hardening stainless steel with chromium, nickel and copper content. It is mainly applied to the fields of aerospace, airplane parts and military industry relying on its good surface smoothness, dimensional stability, machining technology, mechanical property and general corrosion resistant.

　　There is 0.15-0.45 percent of Nb content in this grade which is not easy to be oxidized in the air. However, It shows shat there will be certain burning loss for Nb content in actual ESR process. So how to guarantee stability of Nb content in ESR process is the main technological difficulty. After sufficient technical preparation and argument of the technical staff, they made special measures to preventing oxidation of Nb content and successfully produced 4 tonners of grade 15-5PH ESR ingot with size of Ф600mm which diversified remelting products of Xingtai Steel.