--- title: "Heat Treat Chemicals" url: "https://www.kolene.com/product/heat-treat-chemicals/" description: "Iso-Heat® neutral hardening salts, Iso-Therm® martempering and austempering quench salts, Iso-Braze® aluminum brazing salts, and quench oils. Request an SDS." site: "Kolene Corporation" updated: "2026-09-25T04:30:44+00:00" breadcrumbs: "Home > Products > Heat Treat Chemicals" --- # Heat Treat Chemicals Molten Salt Heat Treat Chemistry ## Which Kolene heat treat salt fits my process and temperature range? The catalog groups products by application and lists melt points and working ranges where they are published. Iso-Therm® nitrate-nitrite salts are quench salts for austempering, martempering, and tempering, with grades for non-ferrous heat treating, rubber curing, and heat transfer. Iso-Heat® chloride salts are neutral salts for hardening, annealing, and high-speed steel work, and Iso-Braze® salts are for aluminum brazing. Blackening salts and quenching oils complete the range. Tell us your alloy, temperature range, production rate, and equipment, and we will recommend the heat treat chemistry. We supply heat treat salts and quenching oils for ferrous and non-ferrous metal processing, including austempering and martempering, tempering, neutral salt hardening and annealing, aluminum heat treating and brazing, blackening, rubber curing, and heat transfer. Use the catalog below to compare product families by application. Our [technical service](https://www.kolene.com/service/field-services/) team can help match chemistry, operating range, [bath maintenance](https://www.kolene.com/service/lab-services/), and equipment requirements to your process. ## Products ### Iso-Therm® 135 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-135 Quench salts A eutectic nitrate-nitrite salt mixture that is used for the interrupted or isothermal quenching of austenitized steels (austempering, martempering, marquenching, etc.). Iso-Therm 135 can also be used for tempering or drawing hardened steels. - **Melt point:** 135 °C (275 °F) - **Working range:** 149–593 °C (300–1,100 °F) [Request SDS for Iso-Therm® 135](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20135) ### Iso-Therm® 142 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-142 Quench salts A eutectic nitrate-nitrite salt mixture that is used for the interrupted or isothermal quenching of austenitized steels (austempering, martempering, marquenching, etc.). Iso-Therm 142 can also be used for tempering or drawing hardened steels. - **Melt point:** 142 °C (288 °F) - **Working range:** 149–593 °C (300–1,100 °F) [Request SDS for Iso-Therm® 142](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20142) ### Iso-Therm® 149 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-149 Quench salts A eutectic nitrate-nitrite salt mixture that is used for the interrupted or isothermal quenching of austenitized steels (austempering, martempering, marquenching, etc.). Iso-Therm 149 can also be used for tempering or drawing hardened steels. - **Melt point:** 149 °C (300 °F) - **Working range:** 163–593 °C (325–1,100 °F) [Request SDS for Iso-Therm® 149](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20149) ### Iso-Therm® 165 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-165 Quench salts A eutectic nitrate-nitrite salt mixture that is used for the interrupted or isothermal quenching of austenitized steels (austempering, martempering, marquenching, etc.). Iso-Therm 165 can also be used for tempering or drawing hardened steels. - **Melt point:** 165 °C (330 °F) - **Working range:** 190–593 °C (375–1,100 °F) [Request SDS for Iso-Therm® 165](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20165) ### Iso-Therm® 177 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-177 Quench salts A eutectic nitrate-nitrite salt mixture that is used for the interrupted or isothermal quenching of austenitized steels (austempering, martempering, marquenching, etc.). Iso-Therm 177 can also be used for tempering or drawing hardened steels. Contact us for current specifications. [Request SDS for Iso-Therm® 177](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20177) ### Iso-Therm® 191 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-191 Quench salts A eutectic nitrate-nitrite salt mixture that is used for the interrupted or isothermal quenching of austenitized steels (austempering, martempering, marquenching, etc.). Iso-Therm 191 can also be used for tempering or drawing hardened steels. - **Melt point:** 191 °C (375 °F) - **Working range:** 204–593 °C (400–1,100 °F) [Request SDS for Iso-Therm® 191](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20191) ### Iso-Therm® 220 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-220 Quench salts A eutectic sodium nitrate and potassium nitrate mixture that is used for the heat treatment of non-ferrous alloys such as aluminum, copper, and brass. Iso-Therm 220 can also be used for tempering of steels. It conforms to Military Specification MIL-S-10699B (Class 2). - **Melt point:** 220 °C (430 °F) - **Working range:** 249–593 °C (480–1,100 °F) [Request SDS for Iso-Therm® 220](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20220) ### Iso-Therm® 135 Rubber Curing Salts Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-135-rubber-curing-salts Rubber curing A nitrate-nitrite salt used in the continuous curing (vulcanization) of rubber extrusions. - **Melt point:** 135 °C (275 °F) - **Working range:** 149–302 °C (300–575 °F) [Request SDS for Iso-Therm® 135 Rubber Curing Salts](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20135%20Rubber%20Curing%20Salts) ### Iso-Therm® 135 Heat Transfer Salts Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-135-heat-transfer-salts Heat transfer Used for chemical processing, energy production, and energy recovery. Can also be used in the production of materials such as melamine, acrylonitrile, caustic soda, chlorine, methyl ethyl ketone, and alkyl amine. - **Melt point:** 135 °C (275 °F) - **Working range:** 149–593 °C (300–1,100 °F) [Request SDS for Iso-Therm® 135 Heat Transfer Salts](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20135%20Heat%20Transfer%20Salts) ### Iso-Therm® 142 Heat Transfer Salts Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-142-heat-transfer-salts Heat transfer Used for chemical processing, energy production, and energy recovery. Can also be used in the production of materials such as melamine, acrylonitrile, caustic soda, chlorine, methyl ethyl ketone, and alkyl amine. - **Melt point:** 142 °C (288 °F) - **Working range:** 149–593 °C (300–1,100 °F) [Request SDS for Iso-Therm® 142 Heat Transfer Salts](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20142%20Heat%20Transfer%20Salts) ### Iso-Therm® 220 Heat Transfer Salts Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-therm-220-heat-transfer-salts Heat transfer Used for chemical processing, energy production, and energy recovery. Can also be used in the production of materials such as melamine, acrylonitrile, caustic soda, chlorine, methyl ethyl ketone, and alkyl amine. Contact us for current specifications. [Request SDS for Iso-Therm® 220 Heat Transfer Salts](https://www.kolene.com/sdsrequest/?sds_product=Iso-Therm%C2%AE%20220%20Heat%20Transfer%20Salts) ### Iso-Braze® 460 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-braze-460 Aluminum brazing Aluminum brazing salt used in the fabrication of items such as heat exchangers, wave guides, and aircraft parts. - **Melt point:** 460 °C (860 °F) - **Working range:** 482–649 °C (900–1,200 °F) [Request SDS for Iso-Braze® 460](https://www.kolene.com/sdsrequest/?sds_product=Iso-Braze%C2%AE%20460) ### Iso-Braze® 520 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-braze-520 Aluminum brazing Aluminum brazing salt used in the fabrication of items such as heat exchangers, wave guides, and aircraft parts. - **Melt point:** 516 °C (960 °F) - **Working range:** 538–649 °C (1,000–1,200 °F) [Request SDS for Iso-Braze® 520](https://www.kolene.com/sdsrequest/?sds_product=Iso-Braze%C2%AE%20520) ### Iso-Blackening Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-blackening Blackening Produces a black oxide finish on steel parts at low temperatures. This makes it suitable for tools, gauges, and other finished parts. - **Working range:** 132–146 °C (270–295 °F) [Request SDS for Iso-Blackening](https://www.kolene.com/sdsrequest/?sds_product=Iso-Blackening) ### Iso-D-Blackening Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-d-blackening Blackening Produces a black oxide finish on steel parts. Also used for isothermal quenching or tempering and for removing rubber from steel molds. Contact us for current specifications. [Request SDS for Iso-D-Blackening](https://www.kolene.com/sdsrequest/?sds_product=Iso-D-Blackening) ### PT Quench Oil 100 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-pt-quench-oil-100 Quenching oils A quenching oil that gives faster cooling rates than straight quenching oils. Normal operating range: 60–88 °C (140–190 °F). [Request SDS for PT Quench Oil 100](https://www.kolene.com/sdsrequest/?sds_product=PT%20Quench%20Oil%20100) ### Park Martemp Oil Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-park-martemp-oil Quenching oils A martempering oil with medium viscosity and a medium quenching speed throughout its range. It is formulated to give extended life during its use as a martempering and tempering oil. Contact us for current specifications. [Request SDS for Park Martemp Oil](https://www.kolene.com/sdsrequest/?sds_product=Park%20Martemp%20Oil) ### Iso-Heat® 454 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-454 Neutral salts A chloride salt mixture that is used for many steel heat treating operations, solution heat treating of non-ferrous alloys, and quenching/tempering for high-speed steels. - **Melt point:** 454 °C (850 °F) - **Working range:** 490–677 °C (914–1,251 °F) [Request SDS for Iso-Heat® 454](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20454) ### Iso-Heat® 454 MPR Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-454-mpr Neutral salts A chloride salt mixture that is used by itself or as a melt point reducer for Iso-Heat 454 and Iso-Heat 493 salt. - **Melt point:** 510 °C (950 °F) - **Working range:** 524–677 °C (975–1,251 °F) [Request SDS for Iso-Heat® 454 MPR](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20454%20MPR) ### Iso-Heat® 482 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-482 Neutral salts A chloride salt mixture that is used for quenching and/or tempering high-speed steels and annealing non-ferrous alloys. Contact us for current specifications. [Request SDS for Iso-Heat® 482](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20482) ### Iso-Heat® 493 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-493 Neutral salts A chloride salt mixture that is used for many steel treating operations such as hardening, annealing, high-temperature drawing, hot quenching of alloy tool steels, and tempering. Contact us for current specifications. [Request SDS for Iso-Heat® 493](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20493) ### Iso-Heat® 549 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-549 Neutral salts A chloride salt mixture that is used for hardening, annealing, and normalizing carbon and alloy steels. It is also suited for preheating high-speed steel tools. - **Melt point:** 549 °C (1,020 °F) - **Working range:** 593–927 °C (1,100–1,700 °F) [Request SDS for Iso-Heat® 549](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20549) ### Iso-Heat® 635 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-635 Neutral salts A chloride salt mixture that is used for hardening, annealing, and normalizing carbon and alloy steels. It is also suited for preheating high-speed steel tools. - **Melt point:** 635 °C (1,175 °F) - **Working range:** 704–1,038 °C (1,300–1,900 °F) [Request SDS for Iso-Heat® 635](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20635) ### Iso-Heat® 665 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-665 Neutral salts A chloride salt mixture that is the most economical and commonly used neutral salt for heat treating within its working range. - **Melt point:** 665 °C (1,229 °F) - **Working range:** 705–900 °C (1,301–1,652 °F) [Request SDS for Iso-Heat® 665](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20665) ### Iso-Heat® 788 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-788 Neutral salts A chloride salt mixture that is used for preheating high-speed tool steels, hardening high carbon-high chromium steels, and hardening or annealing stainless steels. - **Melt point:** 788 °C (1,450 °F) - **Working range:** 843–1,149 °C (1,550–2,100 °F) [Request SDS for Iso-Heat® 788](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20788) ### Iso-Heat® 871 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-871 Neutral salts A chloride salt mixture that is used for forging, normalizing, annealing, hardening, or brazing alloy steels. It conforms to Military Specification MIL-S-10699B (Class 6). - **Melt point:** 871 °C (1,600 °F) - **Working range:** 927–1,260 °C (1,700–2,300 °F) [Request SDS for Iso-Heat® 871](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20871) ### Iso-Heat® 955 Link: https://www.kolene.com/product/heat-treat-chemicals/#chemical-iso-heat-955 Neutral salts A chloride salt mixture that is used for high-speed tool hardening and forging heating steels. It conforms to Military Specification MIL-S-10699B (Class 7A). - **Melt point:** 955 °C (1,750 °F) - **Working range:** 1,038–1,316 °C (1,900–2,400 °F) [Request SDS for Iso-Heat® 955](https://www.kolene.com/sdsrequest/?sds_product=Iso-Heat%C2%AE%20955) ## Safety data sheets (SDS) For current handling, storage, and safety details, request the latest SDS packet for your product. [Request SDS](https://www.kolene.com/sdsrequest/) ## Chemical emergency contact For chemical emergencies, contact CHEMTREC 24/7. [1-800-424-9300](tel:+18004249300) ### Need help choosing heat treat chemistry? Tell us your alloy, temperature range, production rate, and equipment, and we will recommend the right heat treat chemistry. [Contact us](https://www.kolene.com/contact/?interest=Chemicals) KOLENE®, ISO-THERM®, ISO-HEAT® and ISO-BRAZE® are registered trademarks/service marks of Kolene Corporation.