Abstract: An iron-based alloy includes (in weight percent) carbon from about 1 to about 2 percent; manganese up to about 1 percent; silicon up to about 1 percent; nickel up to about 4 percent; chromium from about 10 to about 25 percent; molybdenum from about 5 to about 20 percent; tungsten up to about 4 percent; cobalt from about 17 to about 23 percent; vanadium up to about 1.5 percent; boron up to about 0.2 percent; sulfur up to about 0.03 percent; nitrogen up to about 0.4 percent; phosphorus up to about 0.06 percent; niobium up to about 4 percent; iron from about 35 to about 55 percent; and incidental impurities. The chromium/molybdenum ratio of the iron-based alloy is from about 1 to about 2.5. The alloy is suitable for use in elevated temperature applications, such as valve seat inserts for combustion engines.

Abstract: An iron-based alloy includes, in weight percent, carbon from about 2 to about 3 percent; manganese from about 0.1 to about 0.4 percent; silicon from about 0.3 to about 0.8 percent; chromium from about 11.5 to about 14.5 percent; nickel from about 0.05 to about 0.6 percent; vanadium from about 0.8 to about 2.2 percent; molybdenum from about 4 to about 7 percent; tungsten from about 3 to about 5 percent; niobium from about 1 to about 3 percent; cobalt from about 3 to about 5 percent; boron from zero to about 0.2 percent; and the balance containing iron and incidental impurities. The alloy is suitable for use in elevated temperature applications such as in valve seat inserts for combustion engines.

Abstract: An iron-based corrosion resistant and wear resistant alloy includes (in weight percentage) carbon from about 1.6 to 3%, silicon from about 0.8 to 2.1%, manganese up to 1.0%, chromium from about 12.0 to 15.0%, molybdenum from about 2.0 to 4.0%, nickel from about 0.2 to 0.8%, copper up to 4.0%, boron up to 0.5%, and the balance including iron and incidental impurities. The alloy is suitable for use in elevated temperature applications such as in valve seat inserts for combustion engines.

Abstract: An iron-based corrosion resistant and wear resistant alloy includes (in weight percentage) carbon from about 1.6 to 3%, silicon from about 0.8 to 2.1%, manganese up to 1.0%, chromium from about 12.0 to 15.0%, molybdenum from about 2.0 to 4.0%, nickel from about 0.2 to 0.8%, copper up to 4.0%, boron up to 0.5%, and the balance including iron and incidental impurities. The alloy is suitable for use in elevated temperature applications such as in valve seat inserts for combustion engines.

Abstract: A nickel-rich wear resistant alloy comprises in weight % 0.5 to 2.5% C, 0.5 to 2% Si, up to 1% Mn, 20 to 30% Cr, S to 15% Mo, 5 to 15% W, 15 to 30% Fe, balance Ni. The alloy can include further alloying constituents such as up to 1.5% each of Ti, Al, Zr, Hf, Ta, V, Nb, Co, Cu, up to 0.5% B and up to 0.5% Mg plus Y. The alloy preferably has a microstructure containing predominantly eutectic reaction phases, fine intermetallic phases and precipitation carbides. For instance, the microstructure may contain Cr. Ni, W rich intermetallic phases and/or the microstructure may contain uniform lamellar type eutectic solidification structures. The alloy is useful as a valve seat insert for internal combustion engines such as diesel engines. For a valve seat insert containing up to 1.8% C the microstructure preferably is free of primary dendritic carbides. For a valve seat insert alloy containing over 1.8% C the microstructure preferably contains non-dendritic type primary carbides.

Abstract: A chromium-iron alloy comprises in weight %, 1 to 3% C, 1 to 3% Si, up to 3% Ni, 25 to 35% Cr, 1.5 to 3% Mo, up to 2% W, 2.0 to 4.0% Nb, up to 3.0% V, up to 3.0% Ta, up to 1.2% B, up to 1% Mn and 43 to 64% Fe. In a preferred embodiment, the chromium-iron alloy comprises in weight %, 1.5 to 2.3% C, 1.6 to 2.3% Si, 0.2 to 2.2% Ni, 27 to 34% Cr, 1.7 to 2.5% Mo, 0.04 to 2% W, 2.2 to 3.6% Nb, up to 1% V, up to 3.0% Ta, up to 0.7% B, 0.1 to 0.6% Mn and 43 to 64% Fe. The chromium-iron alloy is useful for valve seat inserts for internal combustion engines such as diesel or natural gas engines.

Abstract: A superaustenitic stainless steel comprises in weight %, 0.15 to 0.9% C, 0.2 to 1.3% Si, 0 to 0.45% Mn, 32.5 to 37.5% Cr, 13.5 to 17.5% Ni, 3.2 to 5.5% Mo, 0 to 2% Nb, 0 to 0.5% B, 0 to 2% Zr and 30 to 51% Fe. In a preferred embodiment, the superaustenitic stainless steel consists essentially of, in weight %, 0.5 to 0.9% C, 0.2 to 0.5% Si, 0.2 to 0.4% Mn, 33.0 to 35.0% Cr, 15.5 to 17.5% Ni, 4.0 to 4.5% Mo, 0.7 to 0.9% Nb, 0.07 to 0.13% B, 0 to 0.05% Zr and 40 to 46% Fe. The superaustenitic stainless steel is useful for valve seat inserts for internal combustion engines such as diesel or natural gas engines.

Abstract: A chromium-iron alloy comprises in weight %, 1 to 3% C, 1 to 3% Si, up to 3% Ni, 25 to 35% Cr, 1.5 to 3% Mo, up to 2% W, 2.0 to 4.0% Nb, up to 3.0% V, up to 3.0% Ta, up to 1.2% B, up to 1% Mn and 43 to 64% Fe. In a preferred embodiment, the chromium-iron alloy comprises in weight %, 1.5 to 2.3% C, 1.6 to 2.3% Si, 0.2 to 2.2% Ni, 27 to 34% Cr, 1.7 to 2.5% Mo, 0.04 to 2% W, 2.2 to 3.6% Nb, up to 1% V, up to 3.0% Ta, up to 0.7% B, 0.1 to 0.6% Mn and 43 to 64% Fe. The chromium-iron alloy is useful for valve seat inserts for internal combustion engines such as diesel or natural gas engines.

Abstract: Disclosed herein is a nickel based alloy comprising, in weight percentage: carbon from about 0.5 to about 1.5; chromium from about 25 to about 35; tungsten from about 12 to about 18; iron from about 3.5 to about 8.5; molybdenum from about 1 to about 8; manganese up to about 0.50; silicon up to about 1.0; and the balance nickel and incidental impurities. The alloy is suitable for valve seat insert applications in internal combustion engines.

Abstract: A cobalt-rich wear resistant and corrosion resistant alloy comprises in weight %, 0.5 to 1.2% C, 0.6 to 2.1% Si, 17 to 24% Cr, 27 to 38.5% Fe, 1.4 to 20% W, 3.8 to 9.7% Mo, less than 1% Ni and balance Co. A preferred cobalt-rich alloy comprises in weight %, 0.5 to 0.9 C, 0.75 to 1.15% Si, 17.5 to 20.5 Cr, 27.0 to 32.0 Fe, 12.5 to 16.5 W, 6.25 to 8.25 Mo, 0.45 to 1.00 Ni and balance Co. The alloy preferably has a microstructure free of primary carbides and comprises up to about 50% by volume eutectic reaction phases in a solid solution matrix. The solid solution matrix is an ?Fe-?Co face-centered cubic solution with W, Cr and Mo as solute elements and the eutectic reaction products comprise a (Co,Cr)7(W,Mo)6 phase and an ?Fe-?Co phase. The alloy is useful as a valve seat insert for internal combustion engines such as diesel engines.

Abstract: A superaustenitic stainless steel comprises in weight %, 0.15 to 0.9% C, 0.2 to 1.3% Si, 0 to 0.45% Mn, 32.5 to 37.5% Cr, 13.5 to 17.5% Ni, 3.2 to 5.5% Mo, 0 to 2% Nb, 0 to 0.5% B, 0 to 2% Zr and 30 to 51% Fe. In a preferred embodiment, the superaustenitic stainless steel consists essentially of, in weight %, 0.5 to 0.9% C, 0.2 to 0.5% Si, 0.2 to 0.4% Mn, 33.0 to 35.0% Cr, 15.5 to 17.5% Ni, 4.0 to 4.5% Mo, 0.7 to 0.9% Nb, 0.07 to 0.13% B, 0 to 0.05% Zr and 40 to 46% Fe. The superaustenitic stainless steel is useful for valve seat inserts for internal combustion engines such as diesel or natural gas engines.

Abstract: A cobalt-rich wear resistant and corrosion resistant alloy comprises in weight %, 0.5 to 1.2% C, 0.6 to 2.1% Si, 17 to 24% Cr, 27 to 38.5% Fe, 1.4 to 20% W, 3.8 to 9.7% Mo, less than 1% Ni and balance Co. A preferred cobalt-rich alloy comprises in weight %, 0.5 to 0.9 C, 0.75 to 1.15% Si, 17.5 to 20.5 Cr, 27.0 to 32.0 Fe, 12.5 to 16.5 W, 6.25 to 8.25 Mo, 0.45 to 1.00 Ni and balance Co. The alloy preferably has a microstructure free of primary carbides and comprises up to about 50% by volume eutectic reaction phases in a solid solution matrix. The solid solution matrix is an ?Fe-?Co face-centered cubic solution with W, Cr and Mo as solute elements and the eutectic reaction products comprise a (Co, Cr)7(W,Mo)6 phase and an ?Fe-?Co phase. The alloy is useful as a valve seat insert for internal combustion engines such as diesel engines.

Abstract: A prehardened valve seat insert and a process for forming a prehardened valve seat insert for insertion into a cylinder head or an engine block of an internal combustion engine. The process comprises the steps of (a) forming the valve seat insert; (b) precision machining the valve seat insert to precise tolerances so that the valve seat insert can be installed in one of the cylinder head and the engine block without the need for additional seat machining; and (c) treating the valve seat insert to form a wear resistant surface layer prior to inserting the valve seat insert into one of the cylinder head and the engine block.

Abstract: An iron-based corrosion resistant and wear resistant alloy is addressed. The alloy contains (in weight percent) 1.1-1.4% carbon, 11-14.25% chromium, 4.75-6.25% molybdenum, 3.5-4.5% tungsten, 0-3% cobalt, 1.5-2.5% niobium, 1-1.75% vanadium, 0-2.5% copper, up to 1.0% silicon, up to 0.8% nickel, up to 0.6% manganese, and the balance iron. The alloy is suitable for use in valve seat insert applications.

Abstract: An iron-based corrosion resistant and wear resistant alloy. The alloy can comprise (in weight percent) 0.005-0.5% boron, 1.2-1.8% carbon, 0.7-1.5% vanadium, 7-11% chromium, 1-3.5% niobium, 6-11% molybdenum, and the balance including iron and incidental impurities. Alternatively, the Nb content can be replaced or combined with Ti, Zr, Hf and/or Ta such that 1%<(Ti+Zr+Nb+Hf+Ta)≦3.5. The alloy has improved hot hardness and high temperature compressive strength and is suitable for use in elevated temperature applications such as in diesel valve seat inserts.

Abstract: A method of manufacturing surface treated, prefinished valve seat inserts. The method entails forming the valve seat insert, precision machining the valve seat insert to precise tolerances so that the valve seat insert can be installed in one of the cylinder head and engine block without the need for additional seat machining and treating the valve seat insert with a wear resistant treatment prior to inserting the valve seat insert into on of the cylinder head and engine block.

Abstract: A nickel based alloy is provided which includes, in weight percentage, 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 1 to about 8; manganese up to about 0.5; silicon up to about 1.0; and the balance nickel and incidental impurities. The alloy is useful for internal combustion engine valve seat inserts and the like.

Abstract: An iron-based corrosion resistant and wear resistant alloy is addressed. The alloy contains (in weight percent) 1.1-1.4% carbon, 11-14.25% chromium, 4.75-6.25% molybdenum, 3.5-4.5% tungsten, 0-3% cobalt, 1.5-2.5% niobium, 1-1.75% vanadium, 0-2.5% copper, up to 1.0% silicon, up to 0.8% nickel, up to 0.6% manganese, and the balance iron. The alloy is suitable for use in valve seat insert applications.