Cast iron welding materials and method
AssigneeResearch Corporation
InventorsDavid L. Olson, Alfredo D. Marquez
Life of this patent
Estimating the term…
Abstract
Filler compositions based on manganese and manganese-nickel for the welding of cast iron are disclosed. The filler compositions contain about 15 to 50% manganese and 10 to 35% nickel. The filler compositions may be incorporated into a welding rod or a flux.
Claims16
A welding composition for use in the submerged arc welded of cast iron, said composition consisting essentially of a mixture of nickel, manganese and flux delineated by the cross-hatched area of FIG. 9 in the drawings, said composition, when used with an iron welding wire producing a cast iron weldment having an improved coefficient of thermal expansion ranging from (15 to 20).times.10.sup.-6 /.degree.C. at 850.degree. C. and a fusion zone wherein 1% to 10% of the weld metal matrix is discontinuous carbides.
A welding wire for use in the gas-metal arc welding of cast iron, said welding wire having a composition consisting essentially of a mixture of nickel and manganese delineated by the cross-hatched area of FIG. 9, with the balance iron, said wire and said process producing a cast iron weldment having an improved coefficient of thermal expansion ranging from (15 to 20).times.10.sup.-6 /.degree.C. at 850.degree. C. and a fusion zone wherein 1% to 10% of the weld metal matrix is discontinuous carbides.
A weldment for cast iron resistant to cracking along the fusion zone, said weldment comprising:
- (a) at least one base metal of cast iron, said cast iron base having a heat effected zone of 0.75-0.80 mm as defined by FIG. 9;
- (b) a weldment fusion zone consisting essentially of 13 to 20% manganese, 15% to 35% nickel, 1% to 3% carbon, with the balance iron and diluted base metal;
- (c) said fusion zone having a percentage of austenite and a co-efficient of expansion selected from the ranges delineated by the cross-hatched area of FIG. 9.
A weldment for cast iron resistant to cracking along the fusion zone, said weldment being formed by submerged arc welding or gas-metal arc welding wherein iron and a non-iron metallic mixture is added to a weld pool, said mixture consisting essentially of mixtures of nickel and manganese defined by the cross hatched area of FIG. 9, said weldment having an improved coefficient of thermal expansion of (15-20).times.10.sup.-6 /.degree.C. at 850.degree. C., wherein 1% to 10% of the weld metal matrix is discontinuous carbides.
An improved method of welding cast iron which will avoid cracks along the fusion zone, said method comprising:
- (a) forming a weld pool on one or more pieces of cast iron to be welded;
- (b) protecting the weld pool from oxidation;
- (c) introducing into the weld pool a metallic misture consisting essentially of nickel, manganese and iron wherein the proportions by weight of nickel and manganese are defined by the cross-hatched portion of FIG. 9, the balance essentially iron;
- (d) cooling the weld pool to produce a fusion zone wherein 1% to 10% of the weld metal matrix is discontinuous carbides.
An improvement in the submerged arc method of welding cast iron, said method comprising:
- (a) covering one or more pieces of cast iron to be welded with a mixture consisting essentially of manganese, nickel and flux as defined by the cross-hatched area of FIG. 9;
- (b) introducing an iron rod into said mixture to contact said cast iron;
- (c) passing an electrical current between said iron rod and said cast iron to create a weld pool under said mixture, wherein iron and carbon from said cast iron, iron from said rod, and manganese and nickel from said mixture combine to form an improved weldment having a coefficient of thermal expansion of (15-20).times.10.sup.-6 /.degree.C. at 850.degree. C. wherein 1% to 10% of the weld metal matrix is discontinuous carbides.
An improvement in gas metal arc welding of cast iron, said method comprising:
- (a) creating an electric arc between a welding wire and one or more pieces of cast iron to be welded, said arc forming a weld pool on said cast iron;
- (b) covering a portion of the welding wire and said weld pool with a non-oxidizing gas;
- (c) consuming said weld wire as the weld pool is advanced along said cast iron, said weld wire consisting of essentially a mixture of iron, manganese and nickel as delineated by the cross-hatched area of FIG. 9, the balance being essentially iron;
- (d) cooling said weld pool to form a weldment wherein 1% to 10% of the weld metal matrix is discontinuous carbides.
Dependencies are inferred from the claim text.