GH2907

GH2907 is a Fe-Ni-Co-based precipitation-hardening superalloy with low expansion deformation, which is comprehensively strengthened with the addition of niobium, titanium, silicon and trace boron. The alloy has high strength, low coefficient of expansion, good resistance to cold and heat fatigue and an almost constant modulus of elasticity below 650°C. The Curie point is at 400°C~450°C. The coefficient of expansion of alloys below the Curie point is basically unchanged.

GH2907 Chemical composition：

	Fe	Ni	Co	Ti	Nb	Si	C	Cr	Al	Mn	P	Cu
Min	Bal	35	12	1.3	4.3	0.07
Max		40	16	1.8	5.2	0.35	0.06	1	0.2	1	0.015	0.5

GH2907 Physical properties：

Density	8.28g/cm³
Curie Point	410℃~450℃
Specific heat capacity	20℃,c=431J/(kg·℃)。
Melting point	1332℃~1400℃

Coefficient of linear expansion

θ/℃	α/(10-6℃-1)	θ/℃	α/(10-6℃-I)
20～100	8.4	20～500	8.8
20～200	8.1	20～600	10.0
20～300	7.9	20～700	11.0
20～400	7.8	20～800	12.2

Resilient performance

θ/℃	20	100	200	300	400	500	600	650	700
E/GPa	159			147	145	139	136	130
Ed/GPaT	160	157	159	159	159	159	154	——	148
G/GPa	59.5	59.9	60.6	61.4	62.1	61.2	59.2	58.1	56.8
μ	0.33	0.33	0.32	0.32	0.31	0.32	0.33	0.33	0.33

GH2907 Mechanical properties：

Standard number	Plate (belt) /mm	Heat treatment	θ/℃	Tensile properties			Long-lasting performance		The average number of line expansions20℃~400℃ a/(10-6℃-I)	Curie Point/℃
				σb/MPa	σpo.2/MPa	δ₅/%	σ/MPa	τ/h
				≥				≥
Q/GYB 05067	00.5～4.0	systemB	20	1000	675	10.0			7.2～8.1	400～450
			540	790	520	10.0	750	60
	δ>4.0		20	1035	725	10.0
			540	825	550	10.0	750	60

GH2907 Alloy properties：

Because GH2907 alloy does not contain chromium and aluminum, it has poor oxidation resistance at high temperatures. When used above 700°C for a long time, an appropriate protective coating should be applied.

The surface of GH2907 alloy can be shot peened, and the rotational bending fatigue can be increased by about 18% after shot peening.

GH2907 Uses of alloys：

HuaNickel GH2907 alloy has been used to make parts such as rear casing, load-bearing ring, heat insulation ring, combustion chamber sealing ring, honeycomb seat and turbine outer ring of aero engine high-pressure compressor.

GH2907 Process performance：

Welding process:HuaNickel GH2907 alloy has satisfactory welding performance, and can be welded by argon arc welding, brazing and electron beam welding. Not only the same material can be welded, but also GH4141, GH4169 and other alloys can be welded.

Cutting process: The alloy has good machinability, and can be cut and ground satisfactorily.

Relevant standards：

GJB 5261、 HB 7682、GH907、HB/Z 140、  Q/GYB 05067、GH2907、 Q/GYB 05069、 HGH2907