A surface treatment for stainless steel can change the magnetism of austenitic stainless steel from paramagnetism to ferromagnetism, so the surface treatment can be utilized to manufacture an electromagnetic needle. The electromagnetic needle includes a front end with a needle point and a rear end. Only the front end is treated with the surface treatment to change its magnetism from paramagnetism to ferromagnetism, and the rear end is paramagnetism as usual. For this reason, the electromagnetic needle can be manufactured as one-piece for improving the quality and defect-free rate.一種不鏽鋼表面處理方法可將沃斯田鐵系不鏽鋼由順磁性轉變為鐵磁性，因此上述方法可用以製造一電磁熱消融針，該電磁熱消融針具有一前端部及一後端部，一針尖位於該前端部，僅對該前端部進行表面處理，使該前端部由順磁性轉變為鐵磁性，而該後端部仍保持順磁性，因此可製得一體成形的該電磁熱消融針，以提高其品質及良率。
