Nickel heat-resistant alloys for coatings

Use

VKNA, RP-NiCr16Al6Y, AP-Cr20Ni80, RP-Cr20Ni80, RP-NiCr20Co20Al13, RP-FeCr20Al6Y and others. Me (Fe, Ni, Co)-Cr-Al alloys provide heat-resistant coatings for gas turbine engines and energy equipment. Reduced and water-sprayed powders may be used to produce parts for use in construction using the sintering method.

RP-Ni85Al15 gas-thermal and flame-resistant, durable in water and coating alkali, and as substrata for coatings made from oxides and carbides.

RP-Ni70Al30 flame-resistant and heat-resistant coatings at temperatures of up to 1200 ⁰С, for use in construction parts produced through sintering.

RP-Ni55Ti45 -wear-resistant coatings durable in coating alkali, seawater, in open air at temperatures of up to 600 ⁰С, in construction parts with shape-memory effects produced through sintering.

Methods for coating deposition:

plasma spraying, plasma-jet hard-facing (PTA), gas-fired, detonation and high-speed spraying (HVOF).

Choice of materia is based on the purpose of the coating, the aim of acheiving special properties in the surface of machine and equipment parts, and based on the method for depositing strengthening coatings.

Powder brand Particle shape Base grain	Nominal chemical composition, %
	Basic components and admixtures
	Fе	Сr	Ni	Co	Мо	Al	Other
AP-NiAl5 gas-sprayed, spheroidal	<1,0	-	base	-	-	5	С <0,1, Si, Fe, Mn <1
AP-Cr20Ni80 (Nitrogen atomization) gas-sprayed, spheroidal AP-Cr20Ni80 (Water atomization) water-sprayed, round -40, 20-63, 40-100, 80-160 microns	<1,0	20,5	base	-	-	-	С, Mn <0,1 Si <0,5 О<0,05
RP-Cr20Ni80 reduced, irregular фр. -40, 40-100, 40-160 microns	<0,3	20	base	-	-	-	С <0,06 S <0,01 Si <0,1 O <0,3
RP-FeCr25Al6 reduced, irregular -45, -63, -280 microns	base	25	--	--	--	6	С<0,2 Са, С <0,2
RP-FeCr20Al6Y reduced, irregular -45, -63, -280 microns	base	26	-	-	-	6	С <0,2 Y
RP-FeCr25Al10 reduced, irregular -45, -63, -280 microns	base	25	-	-	-	10	С <0,2
RP-Ni70Al30 reduced, irregular 20-63 microns	<0,2	-	base	-	-	30,5	С <0,07
RP-Ni85Al15 reduced, irregular 20-63, 40-100 microns	<0.2	-	base	-	-	18,5	С <0,07
RP-Ni55Ti45 reduced, irregular 20-63, 40-100 microns	<0,6	-	base	-	-	-	Ti 45 С <0,07
RP-Ni75Al23W (VKNA) reduced, irregular -56 microns	0.2	+	base	+	+	23	chem. comp. by request
RP-NiCr20Al10 reduced, irregular -45, -63, -280 microns	base	20	-	-	-	10	С <0,2
RP-NiCr16Al6Y reduced, irregular -45, -63, -280 microns	-	16	base	-	-	6	Y 0,5 Са, С <0,2
RP-NiCr20Co20Al13 reduced, irregular -40,-63, 40-100 microns	<0,3	20	base	20	-	13	Y Si Nb С 0,01-0,15
RP-NiCr20Si reduced, irregular -40,-63, 40-100 microns	-	20	base	-	-	-	Si 2

Sprayed powders may be delivered with other particle dimensions not presented in the table, in microns: 45-125, -125, 100-140, 100-280, 160-280, 280-400

Properties of NiAl metallides

The basic phase in the material RP-Ni70Al30 is the metallide NiAl (β` - phase >95%), while in RP-Ni85Al15 it is the metallide Ni₃Al (γ`- phase >95%), and in VKNA the metallide Ni₃Al (γ`- phase). The materials' structure in a coating is marked by high resistance to recrystallization during use at high temperatures.

Particle shape

RP-Ni85Al15

VKNA

Particle size

Base fraction 20-63 microns, VKNA powder 56 microns.

The typical average size (conditional diameter) of powder particles is 30-40 microns

Physical-mechanical properties of powders and coatings

VKNA is a heat-resistant super-alloy based on the metallide Ni₃Al, phase-strengthened with admixtures of infusible metalls, which is characterized by outstanding physical and mechanical properties as plasma coatings, by structural thermal stability, heat-resistance and wear-resistance when used as parts in gas-turbine engines at temperatures of 1150-1200 ⁰С.

RP-Ni70Al30 (Ni70Al30)

Smelting temperature 1640 ⁰С. Exclusively high heat-resistance when heated in open air, more than three times greater resistance to corrosion than the common heat-resistant alloy CrNi77TiAlB.

Material	С over a period of 100 hrs
Material	1000	1100	1200
RP-Ni70Al30 (Ni70Al30)	0,06	0,1	0,2
CrNi77TiAlB (NiCr20Ti2,5Al)	0,14	0,36	0,65

RP-Ni70Al30 in plasma coatings is corrosion-resistant in the atmosphere, water and in alkalis (NaOH and KOH solutions).

Surface hardness is approximately 40 HRC; the material forms durable coatings with steel and copper and presses and sinters well in a vacuum

RP-Ni85Al15 (Ni85Al15)

Melting point is 1400 ⁰С; excellent heat-resistance of coatings when heated in open air to 1150 ⁰С; the material and coatings are durable in the atmosphere, water and alkalis.

Hardness of plasma coatings is approximately 300 HB; the material forms durable coatings with steel and copper.