1.三硝水溶液冷却特性测试三硝水溶液是一种过饱和硝盐水溶液,三硝水溶液因有盐存在,工件大量释放的热量破坏了蒸汽膜的稳定性,其泡状沸腾阶段约在600～650℃开始,较水(340℃)早。三硝水不断吸收工件表面热量而汽化沸腾,将工件的热量带走,形成对流热交换。因此,三硝水溶液淬火介质,在奥氏体最不稳定区650～550℃时,其冷却速度比水慢, Trinitrate aqueous solution cooling characteristics test Trinitrate solution is a supersaturated nitrate solution, due to the existence of salt in the three-nitro-solution, the workpiece release a large number of heat destroyed the stability of the steam film, the bubble boiling stage of about 600 ~ 650 ℃, earlier than water (340 ℃). The three nitric acid continuously absorbs the heat on the surface of the workpiece and evaporates and boils away the heat of the workpiece to form a convective heat exchange. Therefore, the quenching medium of trinitrate solution, the most unstable region of austenite 650 ~ 550 ℃, the cooling rate slower than water,