Composite metal articles
First Claim
1. A method of forming a composite article having first and second metal components, wherein said first component is a ferrous metal and said second component is a ferrous metal or cobalt base alloy comprising the steps of:
- (a) applying a flux coating over a substantially oxide-free bond surface of said first component;
(b) preheating said first component in a mould in which said first component is positioned to a preheat temperature of about 350°
C. to about 800°
C.; and
(c) pouring a melt of said second metal to provide said second component, said melt being poured at a superheated temperature and such that said melt flows over said bond surface to thereby displace said flux coating from said bond surface and wet said bond surface, said superheat temperature being substantially in excess of said preheat temperature, whereby said melt raises the temperature of said bond surface to achieve an initial temperature equilibrium between said surface and the melt, and a substantially instantaneous interface temperature therebetween which is at least equal to the liquidus temperature of the melt, such that on solidification of the melt a bond between the components is attained substantially in the absence of fusion of said bond surface.
2 Assignments
0 Petitions
Accused Products
Abstract
A method of forming a composite article having a first and a second metal components, and a resultant composite metal article, wherein a flux coating is applied over at least a substantially oxide-free bond surface of the first component, the first component with said flux coating is preheated and, with said first component positioned in a mould to fill a portion of a cavity of the mould, a melt for providing the second component is poured into the mould so as to flow over said bond surface; the first component being preheated to a first temperature and the melt being poured at a second temperature such that, on flowing over the bond surface, the melt displaces said flux coating and wets said bond surface, and that such initial temperature equilibration between said surface and the melt results in an interface temperature therebetween at least equal to the liquidus temperature of the melt, thereby resulting on solidification of the melt in attainment of a bond between the components.
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Citations
16 Claims
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1. A method of forming a composite article having first and second metal components, wherein said first component is a ferrous metal and said second component is a ferrous metal or cobalt base alloy comprising the steps of:
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(a) applying a flux coating over a substantially oxide-free bond surface of said first component; (b) preheating said first component in a mould in which said first component is positioned to a preheat temperature of about 350°
C. to about 800°
C.; and(c) pouring a melt of said second metal to provide said second component, said melt being poured at a superheated temperature and such that said melt flows over said bond surface to thereby displace said flux coating from said bond surface and wet said bond surface, said superheat temperature being substantially in excess of said preheat temperature, whereby said melt raises the temperature of said bond surface to achieve an initial temperature equilibrium between said surface and the melt, and a substantially instantaneous interface temperature therebetween which is at least equal to the liquidus temperature of the melt, such that on solidification of the melt a bond between the components is attained substantially in the absence of fusion of said bond surface. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
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Specification