Tuffaloy Welding Data

Recommended Uses of Resistance Welding Materials

GROUP A COPPER-BASE ALLOYS

RWMA Class 1 alloy TUFFALOY 88

CADMIUM-COPPER, suited to welding aluminum and magnesium alloys, coated materials, brass and bronze.

Class 1 alloy is superior to pure copper as an electrode material and is recommended as a general purpose material for resistance welding use. It may be used for spot welding electrodes, seam welding wheels and welding fixture components. It is not heat treatable.

RWMA Class 2 alloy TUFFALOY 77

CHROMIUM-COPPER, suited to welding cold-and hot-rolled steels, stainless steel, and low-conductivity brasses and bronzes.

Class 2 alloy is a superior resistance welding electrode material, recommended for high-production operations. It’s used for welding electrodes, projection welding dies, seam welding shafts and bearings, flash and butt welding dies, and current-carrying structural components. Available in forms for use as welding gun arms, welding platens and secondary-circuit structural members. It is heat treatable.

TUFFALOY Z

ZIRCONIUM-CHROMIUM-COPPER is suited to welding galvanized steel and other metallic-coated steel.

This is a specially heat-treated alloy which meets the minimum electrical conductivity and hardness specifications of Class 2 alloy.

RWMA Class 3 alloy TUFFALOY 55 and 55A

NICKEL-COPPER (55) and BERYLLIUM-NICKEL-COPPER (55A) are suited to welding steels having high electrical resistance, such as stainless steel.

Class 3 alloy is recommended for projection welding dies, and flash and butt welding dies. With its higher strength it is also used on highly-stressed current-carrying parts such as electrode shanks and heavy-duty electrode holders. It is heat treatable.

RWMA Class 4 alloy TUFFALOY 44

BERYLLIUM-COPPER has extremely high hardness, and is recommended for projection, flash and butt welding dies. It has lower conductivity than Class 3 alloy but it is harder and more wear resistant. It should be considered where there is concern with high pressure density and severe wear, but where heating, due to its low conductivity, is not excessive.

It is used frequently in the form of inserts, die facings. and seam welder bushings. It is available in the annealed condition which is more readily machined and then subsequently heat treated.

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GROUP B REFRACTORY METAL COMPOSITIONS

RWMA Class 10 TUFFALOY 1W

TUNGSTEN 55%-COPPER 45%, suited for facings and inserts for projection welding electrodes and flash and butt welding dies. It is recommended where (relatively) high electrical conductivity and some degree of malleability is desired.

RWMA Class 11 TUFFALOY 10W

TUNGSTEN 75%-COPPER 25%, suited to similar applications as Class 10, and for facing on electrode forming dies. It is harder than Class 10, and is for general use in projection welding electrodes.

RWMA Class 12 TUFFALOY 20W

TUNGSTEN 80%-COPPER 20%, suited for electro-forming and electro-forging die facings, and for electrode facings used to upset studs and rivets. A material for heavy-duty projection welding electrodes and dies.

RWMA Class 13 TUFFALOY 100W

TUNGSTEN

RWMA Class 14 TUFFALOY 100M

MOLYBDENUM

Class 13 & 14 materials are used primarily for welding or electro-brazing non-ferrous metals having relatively high electrical conductivity. They are suited to cross-wire welding of copper and brass, and for welding copper wire braid to brass or bronze terminals. Special set-ups and procedures are required.

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R.W.M.A. Recommended Electrode Materials for Spot Welding

Using Conventional Spot Welding Methods

Materials indicated in squares are second choice, example

SPECIAL INFORMATION

1. Special conditions required
2. Good practice recommends cleaning before welding
3. If plating is heavy, we strength is questionable.

Data based on Resistance Welding Equipment Standards, Bulletin 16, a publication of the Resistance Welder Manufacturers Association.

TO WELD SIMILAR METALS

FERROUS	Tin Plate Steel		Terne Plate Steel		Galvanized Iron     Zinc Plate		Cadmium Plate  Steel		Chrome Plate Steel		Stainless Steel      18-8 Type		Scaly H.R.     Steel		C.R. Steel H.R. Steel (clean)
READ BLOCK UNDER METAL TO BE WELDED	B	I	A	I	A	I	B	I	A	II	A	III	B	I	A	II
						II						II		II
	I	3	I	3	I	3	I	3	II	3	III		I	2	II
					II						II		II

NON-FERROUS	Aluminum		Aluminum Alloys Duraluminum		Cupro Nickel		Nickel Silver		Nickel		Nickel Alloy Monel Nichome (High Res)		Brass Yellow 25-40% Zinc		Phosphor Bronze Grade A, C & D		Silicon Bronze Everdur Olympic Duronze Herculoy
	B	I	B	I	A	II	B	II	A	II	A	II	B	II	AB	II	AB	II
		II		II
	I	2	I	2	II		II		II		II		II		II		II
	II		II

TO WELD DISSIMILAR METALS

FERROUS ALLOYS	Stainless Steel 18-8 Type		Chrome Plate Steel		Cadmium Plate Steel		Galvanized Iron Zinc Plate		Terne Plate Steel		Tin Plate Steel
Cold Rolled Steel Hot Rolled Steel, Clean	A	II	A	II	B	II	B	I	A	I	B	I
		III								II
	III		II	3	II	3	II	3	II	3	II	3
Tin Plate Steel	B	II	B	II	B	I	B	I	B	I
		III				II				II
	I		I	3	I	3	I	3	I	3
Terne Plate Steel	B	II	B	II	B	I	B	I
						II
	I	3	I	3	I	3	I	3
Galvanized Iron   Zinc Plate	B	II	B	II	B	I
	I	3	I	3	I	3
Cadmium Plate  Steel	B	II	B	II
	I	3	I	3
Chrome Plate Steel	A	III
		II
	II	3

NON-FERROUS ALLOYS	Nickel Alloys		Nickel		Phosphor Broze		Silicon Bronze		Yellow Brass		Nickel Silver
Cupro Nickel	B	II	B	II	B	II	B	II	B	II	B	II
	II		II		II		II		II		II
Silicon Bronze Everdur Olympic Bronze – Herculoy	B	II	B	II	B	II	A	II	B	II
	II		II		II		II		II
Nickel Silver	B	II	B	II	B	II	B	II
	II	1	II		II	1	II
Nickel Alloys	A	II	B	II
								ALUMINUM
	II		II				ALUMINUM ALLOYS DURALUMINUM	B	I
Stainless Steel   8-8 Type	B	II	B	II					II
	III	1	II	3				I	2
	II		III					II

MINIMUM PHYSICAL PROPERTIES FOR R.W.M.A. ALLOYS

MINIMUM PHYSICAL PROPERTIES FOR R.W.M.A. ALLOYS

		CLASS	TUFFALOY   NUMBER	PROPORTIONAL LIMIT TENSION P.S.I.	HARDNESS ROCKWELL	CONDUCTIVITY PER CENT I.A.C.S.	ULTIMATE TENSILE STRENGTH P.S.I.	ELONGATION % IN 2" OR 4"DIAMETER
GROUP ACopper Base Alloys	ROUND RODS Up to 1" diameter	1	88	17,500	65-B	80	60,000	13
		2	77	35,000	75-B	75	65,000	13
		3	55	50,000	90-B	45	100,000	9
	1" to 2" diameter	1	88	15,000	55-B	80	50,000	14
		2	77	30,000	65-B	75	55,000	13
		3	55	50,000	90-B	45	95,000	9
	2" to 3" diameter	1	88	15,000	55-B	80	50,000	15
		2	77	25,000	70-B	75	55,000	13
		3	55	50,000	90-B	45	95,000	9
	BARS Square Rectangular Hexagon Up to 1" thick	1	88	20,000	55-B	80	60,000	13
		2	77	35,000	70-B	75	65,000	13
		3	55	50,000	90-B	45	100,000	9
	Over 1" thick	1	88	15,000	50-B	80	50,000	14
		2	77	25,000	65-B	75	55,000	13
		3	55	50,000	90-B	45	100,000	9
	FORGINGS Up to 1"	1	88	20,000	55-B	80	45,000	12
		2	77	22,000	65-B	75	55,000	13
		3	55	50,000	90-B	45	94,000	9
	1" to 2"	1	88	15,000	50-B	80	40,000	13
		2	77	21,000	65-B	75	55,000	13
		3	55	50,000	90-B	45	94,000	9
	Over 2"	1	88	15,000	50-B	80	40,000	–
		2	77	20,000	65-B	75	55,000	12
		3	55	50,000	90-B	45	94,000	5
	All sizes	4	44	85,000	33-C	20	140,000	0.5
	CASTINGS  All sizes	2	77	20,000	55-B	70	45,000	12
		3	55	45,000	90-B	45	85,000	5
		4	44	60,000	33-C	18	90,000	0.5
		5	66	12 to 16,000	65 to 85-B	10 to 15	65 to 75,000	2 to 10
GROUP BRefractory Metal Compositions	Rods, Bars & Inserts	10	1W		72-B	35	135,000	Ultimate Compression Strength P.S.I.
		11	10W		94-B	28	160,000
		12	20W		98-B	27	170,000
		13	100W		69-A	30	200,000
		14	100M		85-B	30	200,000