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Resistance Welding Electrodes and Holders
Welding electrode alloys are the hard end of the copper family. They are age hardened, they cut slowly, and the temper is the property you are buying. A Class 2 electrode delivered unhardened looks right on the dock and mushrooms in a shift.
We match electrode and holder work with shops that run chromium copper, zirconium copper and beryllium copper, and that know whether to machine before or after heat treatment.
What the part needs
- RWMA class
- Class 1 for aluminum and coated material, Class 2 for general purpose steel welding, Class 3 and 4 for holders and structural parts.
- Alloy
- C15000 for Class 1, C18200 or C18150 for Class 2, C17510 for Class 3, C17200 for Class 4.
- Temper
- TH04 is the usual finished condition. Say whether the shop machines soft and ages, or machines hardened.
- Water cooling
- Deep drilled coolant passages and their seal faces, if the electrode is cooled.
- Taper and fit
- Shank taper to the standard of your welder. Name it.
- Hardness verification
- If required, state the method and where on the part it is measured.
Grades that fit
Published typical values for the alloy, never a promise from a shop. Each grade has its own reference page.
- C18200
Chromium copperRWMA Class 2. The general purpose electrode alloy for welding steel. Around 80 percent IACS after ageing. - C18150
Chromium zirconium copperClass 2 with zirconium. Holds strength at higher temperature than C18200. - C15000
Zirconium copperClass 1. High conductivity, for aluminum, magnesium and coated steel. - C17510
Nickel beryllium copperClass 3. Holders and backing where the part carries load as well as current.
What drives the price
If a quote looks high, one of these is usually the reason, and most of them can be changed on the drawing.
- Alloy and temperHardened tempers are abrasive and slow. Machining soft then ageing is faster but moves dimensions.
- Coolant passagesDeep drilling in copper alloy with sealed ends is its own operation.
- Heat treatmentAn outside process in the middle of the job, with transport and a queue.
- Beryllium handlingClass 3 and 4 alloys need shop controls. Fewer shops, higher price, and it must be declared in the RFQ.
What to put on the drawing
Send these and the quotes you receive will be comparable. The RFQ builder writes the material lines for you.
- RWMA class and UNS number
- Temper on the finished part, and whether the shop performs the heat treatment
- Which dimensions must survive heat treatment
- Shank taper standard
- Coolant passage geometry and seal faces
- Hardness or conductivity verification if required
- A clear note if the alloy contains beryllium
Send the drawing
Short version here, or the full RFQ form with tolerance, finish and plating fields. Your files go only to the shops we match. Ask for an NDA and nothing moves until it is signed.
We are a matching service, not a machine shop. How matching works.
Questions buyers ask
Something else? Email .
What is the difference between Class 1 and Class 2 electrodes?
Class 1 is more conductive and softer, for aluminum and coated material. Class 2 trades some conductivity for hardness and is the general purpose choice for steel. Class 1 is usually zirconium copper, Class 2 chromium or chromium zirconium copper.
Why does the electrode need a temper?
Because these alloys are age hardened. The hardness that stops a tip mushrooming only exists after heat treatment. An unhardened electrode is the wrong part even if every dimension is correct.
Should the electrode be machined before or after ageing?
Both are done. Soft is easier and moves slightly during ageing. Hardened is slower and holds dimension. Tell the shop which dimensions are critical and let it plan the sequence.
Do you match beryllium copper electrode work?
Yes, with shops set up for it. Declare beryllium copper in the RFQ so shops without the controls decline early.