Article Archive

Finding a Heat Treater

20th Jul 2010   In Article Archive

CHTA Secretary Alan J. Hick offers guidance to those using the Association's website to identify members able to fulfil their specific heat treatment requirements.

Clicking on "Find a Heat Treater" on the Contract Heat Treatment Association's website at takes the visitor looking to outsource to the computerised version of CHTA's much-used authoritative Buyers Guide*.

This constantly-updated database enables easy identification of CHTA members providing specific subcontract heat treatment services in the North, Midlands and South geographical areas of the UK.

Selection, based on processes offered, materials treated and location, results in a list of names of appropriate companies; clicking on each one yields full details of the company, with direct access to its own website. Enquiries can be submitted to one or more of the chosen companies with a single click.

The choice of over forty heat treatment and ancillary processes from which the visitor can select is listed in the following table:

Heat treatment and ancillary processes in "Find a Heat Treater"
  • Ageing
  • Annealing
  • Austempering
  • Austenitic nitrocarburising
  • Boronising
  • Carbon restoration
  • Carbonitriding
  • Carburising
  • Casting core removal
  • Chemical vapour deposition (CVD)
  • Cleaning of paint/plastic deposits
  • Diamond-like coating (DLC)
  • Electron beam treatment
  • Ferritic nitrocarburising
  • Flame annealing
  • Flame hardening
  • Furnace brazing
  • Hardening
  • Homogenising
  • Hot isostatic pressing (HIP)
  • Hydrogen de-embrittlement
  • Induction annealing
  • Induction or torch brazing
  • Induction hardening
  • Ion implantation
  • Malleablising
  • Martempering
  • Nitriding
  • Normalising
  • Physical vapour deposition (PVD)
  • Precipitation hardening
  • Press quenching
  • Shot blasting
  • Shot peening
  • Sintering
  • Solution treatment
  • Steam treatment
  • Straightening
  • Stress relieving
  • Stress relieving on site
  • Sub-zero treatment
  • Sulf BT
  • Tempering
  • Toyota diffusion (TD) process

Where appropriate, the visitor can refine the search in order to select the preferred medium in which a heat treatment is conducted, the choice being: air or products of combustion; controlled/protective gas atmosphere; fluidised bed; pack; plasma; salt; or vacuum/low-pressure processing.

For example, carburising is now mainly conducted in a controlled gas atmosphere (normally based on endothermic gas or nitrogen/methanol mixtures), fluidised beds, salt baths or at low pressure in vacuum furnaces.

Similarly, nitriding is carried out in a variety of processing media including: controlled gas atmosphere (based on anhydrous ammonia); fluidised beds; salt. A further option here is low-pressure plasma nitriding, sometimes known by tradenames like Ionitriding, Eltropuls, PlasNit, ASPN, etc.

This last observation highlights a problem that a visitor to "Find a Heat Treater" might sometimes encounter. By and large, the database uses generic terms to describe the processes offered. Thus, for example, the common tradename Tufftride does not appear in the process list. This salt-bath treatment falls under the generic process name "ferritic nitrocarburising", along with a host of other tradenames for similar processes performed in salt, gas atmosphere, fluid bed or plasma/vacuum, such as Arcor, Nitrotec, Nitemper, Nitral, etc.

Similarly, the "Find a Heat Treater" database does not incorporate outmoded process descriptions such as "cyaniding" or "cyanide case-hardening". Nowadays, salt-bath carburising/carbonitriding is conducted in a more eco-friendly manner.

All companies featured in the database are members of the CHTA and, as such, are pledged to maintain the highest standards of quality and service. ISO 9001 is currently the universally-accepted quality accreditation, but many members hold additional quality approvals from major organisations, which are especially relevant in particular market sectors.

National and international accreditations/certifications held by CHTA members are now listed on the "Approvals" page of the website.

Ask the Members
Another helpful feature of CHTA's enhanced website is the "Ask the Members" page. Where a job is proving difficult to source (say, because of size or other special requirements), this facility allows the visitor to enquire if CHTA members can offer appropriate capacity.

Once submitted, such an enquiry is e-forwarded automatically and instantly to all CHTA members; any able to assist contact the visitor directly.

Using a Contract Heat Treater
In order to benefit fully from the services of a company featured in "Find a Heat Treater", it is recommended that buyers of contract heat treatment should involve the intended supplier at the earliest moment.
CHTA member companies have a wealth of experience in heat treatment which can:
• make a positive contribution in the selection of the most appropriate treatment;
• warn of possible pitfalls;
• help avoid costly mistakes.
But all of this can only happen if the visitor chooses to draw upon this expertise and specialist knowledge.

Specifying Heat Treatment
Clicking on "Specifying Heat Treatment" or "Datasheets" accesses CHTA's series of Datasheets for Non-heat-treaters, aimed at aiding sensible specification of subcontract heat treatment processing and avoidance of common problems. Couched in layman's terms, they answer the questions: What are the treatments? What are the benefits? What materials can be treated? What are the limitations? What problems could arise? How do I specify? Where do I go?

In response to the last question, the datasheets recommend contact with appropriate CHTA member companies from those listed at

*For a free hard copy of the 8-page Buyers Guide to Contract Heat Treatment (10th edition), contact Nasima Khatun at the Contract Heat Treatment Association, c/o SEA, BJGF Federation, Federation House, 10 Vyse Street, Birmingham B18 6LT (tel: 0121 237 1123; e-mail:; fax: 0121 237 1124).