DZ422

HuaNickel DZ422 is a nickel-based precipitation hardening directional solidification column-crystal superalloy with a service temperature of less than 1050°C, which is one of the alloys with the highest performance level in China. The alloy has good comprehensive properties of medium and high temperatures, as well as excellent resistance to cold and heat fatigue. The alloy contains 1.5% w(Hf) to improve the strength of the alloy Transverse and make it have good casting properties, and can be cast into notBal directional solidified hollow blades with complex cavities with wall thicknesses as small as 0.5mm, which are suitable for making gas turbine rotor blades and guide vanes and other high-temperature parts.

DZ422chemical composition：

	Ni	C	Cr	Co	W	AI	Ti	Nb	Hf	Zr	Si	P	Mn	S	Cu
Min	Bal	0.12	8	9	11.5	4.75	1.75	0.75	1.4	≤
Max		0.16	10	11	12.5	5.25	2.25	1.25	1.8	0.05	0.15	0.01	0.2	0.015	0.1

DZ422Physical properties：

Density	7.56g/cm³
Melting point	1230℃~1240℃
Magnetic properties	not

Specific heat capacity

θ/℃	20	100	200	300	400	500
c/[J/(kg·℃)]	385	393	398	423	456	494
θ/℃	600	700	800	900	1000	1100
c/[J/(kg·℃)]	540	573	599	624	645	666

Coefficient of linear expansion

θ/℃		28～300	28～400	28～500	28～600	28～700	28～800	28～900	28～1000	28～1100
α/(10-6℃-1)	Longitudinal	11.37	12.57	12.85	13.01	13.63	14.08	14.60	15.44	16.58
	Transverse	11.46	12.69	12.90	13.10	13.60	13.96	14.75	15.48	16.71

Resilient performance

θ/℃		20	100	150	200	300	400	450	500	600	700	730	750	800	850	900	950	1000	1050
Ed/GPa	Longitudinal	130	128		126	123	119		116	112	107			102		96		88	72
E/GPa	Longitudinal	132						—					102		88.5		77.8
	Transverse	155								—			131		110		104
G/GPa	Longitudinal	127											105		101		94
μ	Longitudinal	0.336		0.337		0.342		0.348		0.351		0.353			0.354
	Transverse	0.476		0.475		0.467		0.483		0.468	—	0.476			0.477

DZ422Mechanical properties：

Standard number	variety	Sampling	θ/℃	Tensile properties			Long-lasting performance
				σb/MPa	δ₅/%	ψ/%	σ/MPa	τ/h	δ₅/%
HB 7762	Master alloy	Directional solidification test sticksLongitudinal Standard heat treatment	20	≥980	≥5	≥5		—
			760	—	—	—	690	48	≤4
			980				220	20	≤22
				—		—		≥32	≥10

DZ422Alloy properties：

The surface of the part can be treated with Al or Al Si coating, which can significantly improve the oxidation resistance and hot corrosion resistance of the alloy. After the alloy is aged for a long time at 850 °C ~ 950 °C, a small amount of μ phase is precipitated.

DZ422Uses of alloys：

HuaNickel DZ422 alloy has been used in the manufacture of gas turbine rotor blades working below 1000 °C and guide vanes working below 1050 °C in aero engines, and is well used. Foreign similar alloys are widely used in the manufacture of various advanced aero engine rotor blades and guide vanes.

DZ422Application field process performance：

Welding process: vacuum brazing can be carried out, and the performance of the brazing joint reaches 60%~80% of the performance of the base metal.

Surface Treatment: Parts can be treated with Al or Al Si coating.

Relevant standards：

GB/T14992 、HB 7762 、HB/Z140