Nickel based alloys for internal combustion engine valve seat inserts, and the like

A valve seat insert for use in an internal combustion engine, said valve seat insert made of an alloy consisting essentially of in wieght percent:

• carbon from about 2 to about 3;
• chromium from about 30 to about 40;
• tungsten from about 12 to about 18;
• iron from about 3.5 to about 8.5;
• molybdenum from about 4 to about 5;
• manganese up to about 0.5;
• silicon up to about 1.0;
• and
• the balance nickel and incidental impurities.

A nickel based alloy consisting essentially of in weight percent:

• chromium from about 34.0 to about 37.0;
• iron from about 5.0 to about 7.0;
• molybdenum from about 4 to about 5;
• and
• the balance nickel, other metals, and incidental impurities;
• wherein the chromium, iron, and molybdenum content of the alloy increase the fineness and uniformity of the microstructure of the alloy thereby resulting in the alloy having increased hardness and compressive yield strength.

A cast alloy comprising chromium, nickel, tungsten, iron and molybdenum, wherein the relative concentration of Cr, Ni and W is such that a three-phase eutectic composition is capable of forming at a temperature of about 800° C., the alloy consisting essentially of in weight percent:

• molybdenum from about 4 to about 5,
• chromium from about 30 to about 40, and
• tungsten from about 12 to about 18,
• and the alloy further comprises carbon from about 2 to about 3 weight percent.