Abstract: High chromium steel, for use at high temperature, of a mixed structure containing ferrite and 0.02-0.09% C, less than 1.0% Si, 0.1-2.0% Mn, 7.0-13.0% chromium, 1.2-3.0% Mo, and the rest being iron and the usual impurities, or further adding aluminum in an amount less than 0.1% to said composition, or further adding 0.001-0.1% boron and less than 0.1% Ti necessary to cause the boron to act effectively, said steel being heated at temperatures lower than about 1050.degree. C. to prevent the oxidation of the steel.

Abstract: A method of sintering ferrous materials comprises mixing an iron powder with an alloy of iron-titanium and forming a liquid phase during the sintering. The alloy is prepared by mixing selected amounts of iron and titanium powders to form an iron-titanium alloy powder consisting essentially of 14 to 46% by weight of titanium and the balance iron, and preferably 14 to 30% by weight of titanium. The sintering step is carried out at a temperature at which the powdered mixture is always in the liquid phase during sintering. Under these conditions oxidation of titanium is suppressed during melting and the alloy is not too soft nor too difficult to pulverize and used for manufacturing the machine components such as piston rings which have surprisingly good properties due to the use of the critical amounts of iron and titanium in the alloys useful according to the invention.