| 摘要 |
A method is disclosed for increasing physical properties of a non-allotropic metal article along a beam affected zone. A preferred method comprises passing a high energy beam (of at least 10,000 watts/cm2 measured at the interface of the beam with the article across a predetermined surface area at a rate to cooperate with the proportioning of the total article mass with respect to the beam affected zone mass to produce a rapid self-quenching rate and thus assure a desired precipitate and/or intermetallic compound in the resolidification zone. The high energy beam is preferably a laser generated by a device having a power level of at least 500 watts. The method requires and facilitates alloying which may be varied in several respects: (a) alloying ingredients may be previously deposited over the beam affected zone so as to be turbulently mixed with melting of the base material in said zone, (b) alloying ingredients may be constituted as a wire and fed into the high energy beam to be contemporaneously melted with the base material, (c) the alloying ingredients are selected as those having an affinity to form intermetallic compounds with the non-alloptropic metal base, such as copper, manganese, chromium, zinc, cobalt, magnesium, molybdenum, titanium, vanadian, tungsten, zirconium, iron and nickel for an aluminum base and silicon as an independent wear resistance particle, and (d) the alloying ingredients are proportioned with respect to the thickness of the melted zone to render a desired alloy concentration after melting to facilitate greater hardness, greater corrosion resistance, or greater fatigue life of the affected surface region of the article.
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