Abstract: The present invention relates to powder particles consisting of hard principles and binder metal for the manufacture of superior, uniquely fine-grained hard material alloys and to a procedure for the preparation of said particles.The preparation is performed in an economical way because the procedure starts from conventional melt metallurgical raw materials. A pre-alloy consisting of hard principle forming and binder phase forming elements is subjected to a heat treatment such as nitriding and carburizing after being crushed. The final product is particles composed by hard principle phases and binder metal phases formed "in situ" in an effective binding.

Abstract: The present invention is directed to air-meltable, castable, weldable, machinable alloys of reasonable ductility and resistance to very hot concentrated sulfuric acid as well as to most other more dilute strengths of the acid either in the pure acid-water forms or containing additionally contaminants that might be encountered in practical applications. The alloys consist essentially of between about 36% and about 40.5% by weight nickel, from about 31% to about 33% by weight chromium, from about 4% to about 5.2% by weight molybdenum, from about 2.7% to about 4% by weight copper, from about 2.5% to about 6% by weight silicon, from about 0.40% to about 0.62% by weight nitrogen and the balance essentially iron. The instant alloys may also contain up to about 2% by weight manganese and up to 0.11% by weight carbon.