Working group on cooling power test of quenchants of Japanese Heat Treatment Society has studied on the new method for testing cooling power of aqueous quenchants. This method employed the cooling curve test of a new ...Working group on cooling power test of quenchants of Japanese Heat Treatment Society has studied on the new method for testing cooling power of aqueous quenchants. This method employed the cooling curve test of a new sliver rod probe, which has a metal-sheathed thermocouple at its geometrical center. The experimental study has clarified that the new silver probe has more excellent durability than the JIS silver probe employed for cooling power test of heat treating oils (JIS K 2242) and an aluminum alloy probe. Good repeatability and reproducibility of the cooling curves during polymer quenching have been confirmed. This new method is useful especially for cooling power test of aqueous quenchants used for solution heat treatment of aluminum alloys. This new silver rod probe is expected to be adopted for the revised version of JIS K 2242 as the cooling power test method for aqueous quenchants.展开更多
Quenching Oils are comprised mostly of mineral oil as major component, but mineral oil alone result in lower cooling performance. Therefore, various additives are formulated as required for each particular case. Cooli...Quenching Oils are comprised mostly of mineral oil as major component, but mineral oil alone result in lower cooling performance. Therefore, various additives are formulated as required for each particular case. Cooling curves of mineral oil as determined by JIS method can be divided into three stages, vapor film stage, boiling stage and convection stage. And there are many types of additives used for quenching oil, one effective to shorten vapor film stage and another to shift boiling stage toward lower temperature side. As rapid quenching required temperature range for particular steel varies pending on its shape of CCT curve"1, it is possible to provide higher quench hardening performance using quenching oil formulated of adequate additives.展开更多
文摘Working group on cooling power test of quenchants of Japanese Heat Treatment Society has studied on the new method for testing cooling power of aqueous quenchants. This method employed the cooling curve test of a new sliver rod probe, which has a metal-sheathed thermocouple at its geometrical center. The experimental study has clarified that the new silver probe has more excellent durability than the JIS silver probe employed for cooling power test of heat treating oils (JIS K 2242) and an aluminum alloy probe. Good repeatability and reproducibility of the cooling curves during polymer quenching have been confirmed. This new method is useful especially for cooling power test of aqueous quenchants used for solution heat treatment of aluminum alloys. This new silver rod probe is expected to be adopted for the revised version of JIS K 2242 as the cooling power test method for aqueous quenchants.
文摘Quenching Oils are comprised mostly of mineral oil as major component, but mineral oil alone result in lower cooling performance. Therefore, various additives are formulated as required for each particular case. Cooling curves of mineral oil as determined by JIS method can be divided into three stages, vapor film stage, boiling stage and convection stage. And there are many types of additives used for quenching oil, one effective to shorten vapor film stage and another to shift boiling stage toward lower temperature side. As rapid quenching required temperature range for particular steel varies pending on its shape of CCT curve"1, it is possible to provide higher quench hardening performance using quenching oil formulated of adequate additives.
