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For additional information, call (812) 379-4243 or contact your Tool Dynamics representative.

What is TDX Coating?

TDX (Thermo-Reactive Diffusion) is a coating process that diffuses a layer of carbides onto and into the surface of the tooling. The TDX layer is metallurgically bonded to the tooling, providing superior adhesion strength and dramatically extending the life of your tooling. High adhesion strength and a hardness of 4200+ Vickers make the TDX Coating ideally suited for high-pressure and high-abrasion metal forming. This coating has a reputation for providing outstanding results to Tool Dynamics customers with severe applications. View our TDX Coating description page for more information.

Does TDX really work?

Every application is different, and some applications are better candidates for the TDX Process than others. Call us at (812) 379-4243 with your situation and we will give you an honest evaluation of what you can expect. Click here to see some of our customers' success stories.

Why use TDX instead of PVD or CVD?

  • The Process: TDX diffuses the coating both onto and into the surface of the substrate. PVD and CVD processes deposit coatings onto the surface of the substrate in a vacuum chamber. The Thermal Diffusion Process provides superior adhesion, durability, peel strength and lifespan to finished products when compared to deposition processes.
  • The Coating: The Vanadium/Niobium Carbide layer (diffused by the TDX process) has superior hardness to PVD and CVD layers. Higher hardness equals greater durability, wear resistance and lifespan.

What are the benefits of TDX Coating?

TDX Coating . . .

  • extends tool life
  • decreases maintenance time and expense by reducing galling and wear
  • can reduce the amount of lubricant needed
  • increases press up-time
  • improves the quality of parts and their surface finishes

Which applications should TDX Coating be used for?

There are many potential applications, including tooling and component parts. Here are some in the metal-forming industry:

  • Stainless-Steel Forming
  • Tube Forming and Bending
  • Extrusion
  • Deep Draw Dies
  • Form Blocks
  • Curling
  • Flange Dies
  • Swaging
  • Flaring
  • Ironing
  • Sizing
  • Piercing Tools
  • Cold & Hot Forging
  • Roll Forming
  • Die-Casting
  • Stab Blades
  • Fine Blanking
  • Shearing
  • Rollers
  • Expanding Punches
  • Mandrels
  • Hydro-Forming Tooling
  • Any other tooling which exhibits wear, galling or sticking.

What is customer service like at Tool Dynamics and the TD Center?

  • Accessible. We have a knowledgeable and dedicated sales staff fully committed to helping you and answering your questions. See for yourself and contact us live by phone at (812) 379-4243 between 8AM and 5PM on weekdays, or leave us a voicemail message at any other time and we will return your call as soon as we can. To contact a specific individual, find our representatives' and specialists' e-mails and phone numbers on our Contact Us page.
  • Flexible Delivery Options. FedEx, UPS, Ground, Air or Door-to-Door—tell us your preference and we will follow through.
  • Broad Range of Payment Methods. We take all major credit cards as well as wire transfers and checks. Read the next two questions' answers for more information.

How do I set up an account with Tool Dynamics and the TD Center?

We do a Dun and Bradstreet credit check on all new customers prior to processing their order. To avoid delays on your order, please call us in advance to start this process.

If your credit check passes our approval, we immediately enter your company in our system and start processing your order. No order ships without a purchase order number.

If your company has a D&B credit rating of a 4 (poor) or 3 (fair) with a downward trend, your company is automatically put on payment-in-advance. We cannot begin processing your order until we receive your payment. We accept payment-in-advance via check, wire transfer, and major credit cards.

If you do not have a credit rating with D&B, then we require you to fill out a credit application form. We require credit references from your bank and other suppliers to determine what level of credit, if any, we can extend. We encourage you to take these steps prior to your first order since this process takes time.

What are the payment options?

For customers that meet our credit requirements, we extend credit terms as Net 30. This means that any invoice during a given month requires payment within the next thirty days. For example, an invoice dated the 22nd of April is due on the 22nd of May.

From all other customers, we accept all major credit cards, wire transfers and checks.

What is the shipping address of Tool Dynamics and the TD Center?

Tool Dynamics
835 South Marr Rd.
Columbus, IN 47201

You can call us at (812) 379-4243 or fax us at (812) 379-4222 as well.

What is the preferred method for shipping parts to Tool Dynamics and the TD Center?

For smaller orders, we prefer to receive shipments via UPS. We also receive shipments via FedEx, Airborne, Emery Worldwide, DHL, etc.

For larger shipments, we can receive your order via your normal trucking company.

For expedited, door-to-door service, we offer pick-up and delivery in Indiana and surrounding states. Call (812) 379-4243 for details.

Why do I need to fill out a Quotation Request / Process Sheet?

It allows you to communicate clearly with us about your tooling, enabling us to produce the best possible results for you and your application. You do not have to fill one out in order to get work done (if you prefer, you can call or fax in the details instead), but a completed process sheet does speed up the operation. Here are some of the other advantages it provides:

  • Viability Checking. We are able to verify whether your tooling can be processed.
  • Size Movement Prevention. The TDX process is performed at high temperatures, so some size movement in the steel is likely to occur. This is directly related to steel type and previous heat treatment. We use the history of your tooling (specifically its heat treatment history) to prevent or minimize potential issues that arise during processing.
  • Well-Informed Decision Making. With adequate information, we can verify whether the process selected is right for your application. In addition, the information you provide about the materials your tooling will ultimately form or work tells us whether we need to further enhance the substrate's ability to support its coating.

If you choose give us the information by phone or fax instead, we need at least the following: steel type, special processing instructions, a purchase order number, and a ship-to address.

Where can I get a Quotation Request Form / Process Sheet?

You can access it here or from our home page.

What about shipping and packaging?

TDX coated tools, received or shipped, are ready-to-use. When sending, pack with a sufficient amount of corrugated cardboard to avoid damage to the part in transport. We discourage the use of plastic bubble wrap, which does not protect the part sufficiently. Parts sent in a “soft” state should be packed with extra care.

How long will it take?

Turn-around time for the TDX Process is typically around 5 to 7 days. Large orders, details needing extensive polishing, high speed or PM steels or dual-layer TDX Supreme coatings can add to the turn-around time. Call us for an estimate if your order includes any of these processes.

What if I need my parts back sooner?

Please make these needs known as you talk to us or fill out the process sheet. Depending on the existing work load at the time, we will attempt to accommodate your needs.

How thick is a layer of TDX Coating?

The TDX Coating is similar in thickness to other thin film coatings—about .00015 to .0003 inches thick.

How hard is TDX Coating?

Thin film coatings like TDX are measured using the Vickers Hardness Test, which describes hardness on a scale from 0 to 6000. The hardness of the TDX layer is about 4200HV to 4500HV. By comparison, although the Rockwell C scale does not extend past 68, TDX would theoretically be 90+ HRC (Hardness Rockwell “C”). Using the Vickers scale, hardened tool steel measures 500HV to 800HV (55 to 65 HRC), Chrome is 600HV to 900HV (60 to 66 HRC) and TiN is 2200HV to 2500HV. The Rockwell “C” Scale cannot be used to accurately measure coatings. Also, the diamond plunge test will not record the contribution of a .0002-to-.0003-inch-thick layer to a surface.

What if the part has been previously coated?

The TD Center can remove TD, TDX, PVD and CVD coatings. Many chrome coatings must be removed via reverse electrolysis. Nitrided surfaces present a more complicated issue, so please discuss the application with Tool Dynamics.

How hot does the TDX Process get?

The coating is diffused in a solution of molten salt at the austenitizing temperature of many tool steels (between 1750 and 1850 °F). Putting the steel in an austenite stage causes carbon to become available, allowing the Vanadium/Niobium Carbide layer to form. Applying the coating at this temperature causes it to be diffused into the surface of the substrate, forming the molecular bond that makes TDX Coating so durable.

Can I send in steel that hasn't been heat-treated?

Yes. The TDX Process will also heat-treat the tool steel. Standard hardnesses of TDX-processed A, D, CPM and M-series steels will be in the 50-to-59 HRC range, and H-series steels will be in the 49-to-54 HRC range. (See these guidelines for selecting tool steel grades for more specific information.) However, “soft” or annealed tool steels are less conducive to optimum surface finishing and have higher potential for dimensional movement in comparison to steels that have been pre-hardened. If full hardness is required, additional vacuum heat treatment can elevate the hardness of the substrate after TDX processing.

Will the TDX Process make the steel too hard?

While the hardness of the TDX coating exceeds Rockwell limits (over 90 HRC), the hardness of the substrate is not affected by the coating layer. The coating is .00015 to .0003 inches thick (depending on the tool steel type) and does not change the ductility of the tool itself. Substrate selection, heat treating and tempering determine the overall hardness of the tool.

Will the TDX Process change the size of my parts?

Some dimensional change may occur—the TDX Process is similar to a heat treat cycle. The precise movement of tool steel during heat treatment is difficult to determine, but information provided by you, along with specific heat-treating and tempering temperatures in the detail's original heat-treat process, can help us to control size movement and produce excellent results. The prints and the process-sheet information you can provide (e.g. part history, critical dimensions and critical tolerances) allow us to predict the behavior of the part during the process.

Note: for jobs with extremely tight tolerances, please contact us prior to final sizing of tooling. Leaving grind stock on non-working areas can facilitate final sizing after the process. Also contact us about machining recommendations for various tool steels.

Will the TDX Process anneal my tool?

No, but it can affect the hardness. The TDX Process is a heat treat process, so soft, air-hardened tool steels will come out of the process in a hardened state. The steel type, heat-treatment history, size and shape of a tool will all determine the substrate's exact hardness after TDX. We offer Post Hardening to increase substrate (core) hardness after coating.

What is Post Hardening?

While the TDX process is performed to create the optimum carbide layer, the process time and quench rates do not always produce the optimum substrate (core) hardness of the steel being treated. If high forming pressures are the working environment for the tool, then “post hardening” in one of our vacuum furnaces is recommended. This process will increase the core hardness of the substrate and improve its ability to support the TDX coating layer. This is especially true with PM and high speed steels that require higher heat treat or tempering temperatures than the TDX process alone provides. For more information, view our technical bulletin on post hardening.

What types of steel can be treated with the TDX Process?

Air-hardened tool steels with 0.3% carbon content or higher can be TDX treated—most H, D, M, A and PM-series tool steels fall into this category. Our process also works well on carbide (10% binder or higher) and on some grades of martensitic stainless steel.

The TDX Process does not work with Anvilloy, TZM, Bronze, or any steel that has been nitrided. However, if a nitrided detail can be machined to remove all nitrided material, it can also become a viable subject for TDX.

Does the grade of steel used make a difference?

Yes. Premium grade steels are highly recommended for the TDX Process; inferior grades may contain impurities that will impede proper finishing or processing.

Is tool maintenance different with a TDX-coated part?


  • TDX Processing typically reduces the amount of maintenance (such as grinding and polishing) required for proper upkeep of tooling.
  • In the event that galling builds up on the TDX layer, do NOT use any conventional hard fiber, carborundum or diamond media to remove it. Instead, use non-aggressive abrasives such as “scotch-brite”-type discs (green or blue fine / very fine), aluminum-oxide papers of 300-through-600 grit or chemicals to remove the buildup. This substitution of cleaning materials protects the TDX layer from damage and in many cases will enable reuse of the detail.

How do you charge for coating parts?

We charge by weight with a tiered scale that depends on the overall size of the order. The more you send in, the cheaper it will be.

How large a part can be treated in the TDX Process?

The part should fit within a cylinder 22 inches in diameter by 24 inches long. Call us at (812) 379-4243 if you have slightly larger parts.

What surface finish is required prior to TDX Coating?

The goal is to polish the working surfaces to a mirror finish of 5-to-8 RMS. Polishing is a very critical step that ensures the best possible performance of our coating. A highly-polished surface reduces friction and improves material flow.

Lowering friction is one of the key steps in:

  • reducing or eliminating the need for lubrication
  • reducing or eliminating galling
  • improving part appearance
  • reducing the amount of maintenance necessary

In addition, a highly polished surface provides better adhesion between TDX Coating and the substrate.

There are several techniques to keep in mind when polishing—for tips and best practices, please refer to our technical bulletin on polishing.

Does Tool Dynamics polish tooling?

Yes. Tool Dynamics offers polishing service. Please call (812) 379-4243 for more information.

After any old coating / surface damage has been removed, traditional stoning with die or moldmaker stones and diamond polishing are performed.

Can the TDX Process be applied more than once?

Yes. The TDX process may be re-applied several times—perhaps 4 to 6 times or more—depending on factors such as tool steel and application type. Please contact us for more information.

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