Polymer Quench Hardening

Polymer quench hardening is an ideal method for hardening machined parts and stampings made from lightly alloyed steels such as 1045, 1144, 1035, or even parts made from some more heavily alloyed steels with difficult mechanical property requirements.  


Therm-Tech runs all polymer quench hardening out of batch-type furnaces, which are ideal for process and lot control.  The largest furnace employed in the this process has internal working dimensions of 88”W x 129”L x 42”H, and our Largest Polymer Quench tank has dimensions of  74” x 103” x 54”.  All of Therm-Tech’s furnaces are certified to AMS 2750, ensuring optimal temperature uniformity during the hardening process.


The process of polymer quench hardening for machined parts and stampings is performed by first fully austenitizing the steel in the temperature range of 1500°F – 1650°F (depending on the alloy) in a surface-protecting carbon controlled atmosphere.  It is held at this temperature for a time commensurate with the part cross section, and then quenched in polymer to produce a fully hardened martensitic microstructure.  After quenching, parts are tempered to specification.

Therm-Tech has the capability to quench into polymers of a variety of concentrations and levels of agitation in order to maximize mechanical properties while minimizing distortion.  However, in cases wherein severe distortion during polymer quench hardening is process prohibitive we recommend oil quench hardening, marquench hardening or austempering services.


Please be aware that lower final hardness ranges that require tempering above 900°F will result in temper oxide formation on most steel grades.  ThermTech offers a variety of blasting services for machined parts to remove any oxide formation and improve the surface finish. For bright finish requirements, ThermTech is also proud to offer vacuum hardening of machined parts with either gas or oil quenching.

ThermTech offers polymer hardening processes for machined parts and stampings for many low-alloy steel grades. Some of the most common materials we offer this process for include:

  • Polymer hardening 1045 steel
  • Polymer hardening 1050 steel
  • Polymer hardening 4140 steel
  • Polymer hardening 1035 steel
  • Polymer hardening 1145 steel

For large volumes of parts and/or to learn more about how our polymer hardening process can benefit your products please contact our sales staff for a formal quote today!