Abstract: Because of practical condition that the microstructure and properties of the TM210A maraging steel didn’t meet the requirements from the standard， the effects of chemical composition and the remelting rates in vacuum consumable electrode on the macrostructure and the mechanical properties of the TM210A steel bars were investigated. The microstructures of the steel bars after solidsolution and aging treatments were observed by transmission electron microscopy (TEM). The experimental results showed that the reasonable control of the contents of the strengthening elements increased the strength of the bar， and the appropriate remelting rate in vacuum consumable electrode also effectively improved the macrostructure quality and the strength of the bar. The smelting processes of the steels were established according to the above results.

Key words: chemical composition, remelting rates, microstructure, macrostructure, mechanical property