| The traditional fabrication of moulds adopts forge blanks and machining which results in lower material availability, e.g. 20%~40% of the total only, and a longer work cycle for the fabrication would be needed.When casting is used to make a mould that can be cast directly to the approximate dimensions can reduce working surplus-over to the maximum. Therefore, this process as an advanced mould making will be most prosperous for its short manufacture cycle, low material consumption, and obvious economic benefit.Steel H13 is typical for the mould making. This project focuses on dealing with heat treatment and relevant problems in steel H13 casting for moulds.Hypereutectoid structure of steel H13 casting was improved through spheroidizing treatment, and the steel structure becomes more even. Spheroidizing treatment process after the test is defined as follows:Heat up the work piece to 880℃±10℃, insulate it for 2h, lower the temp to 750℃±10℃, insulate it again for 4h or so, before cooling it down slowly up to a furnace temp of about 500℃, and deliver the work piece for air cooling.Soft nitriding process was used to further improve surface capability of the mould material, and good application result has been achieved.
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