Hastelloy C-22

HuaNickel Hastelloy C-22 alloy was introduced in 1982, which is an improvement and development of several high-molybdenum Ni-Cr-Mo alloys mentioned above. The newly developed Hastelloy C-22 alloy system increases the chromium content by approximately 21% and reduces the amount of molybdenum by approximately 13%, and an appropriate amount of tungsten (approximately 3%) is added to balance the amount of chromium, molybdenum, and tungsten alloy. Because of these characteristics, Hastelloy C-22 alloy has better corrosion resistance than the aforementioned Ni-Cr-Mo(- W) alloys in many media. In particular, it is more obvious in oxidizing media such as FeCl₃ and CuCl₂, wet chlorine, and redox acids. At the same time, the alloy still has excellent resistance to pitting, crevice corrosion and stress corrosion.

Hastelloy C-22Chemical composition：

	Ni	Cr	Mo	W	Fe	C	Si	Mn	P	S	V	Co
Min	Bal	20	12.5	2.5	2	≤
Max		22.5	14.5	3.5	6	0.015	0.08	0.5	0.04	0.02	0.35	2.5

Hastelloy C-22Physical properties：

Density	Melting point/℃		Specific heat capacity/J·(kg·K)-1					Thermal conductivity/W·(m·K)-1
			52℃		100℃		200℃	48℃		100℃	200℃	300℃
8.69	1359-1399		414		423		444	10.1		11.1	13.4	15.5
Resistivity/μΩ ·m						linear expansion coefficient,/×10-6m·(m·K)-
24℃		100℃		200℃		24～93℃			24～204℃		24～316℃
1.44		1.23		1.24		12.4			12.4		12.6

Hastelloy C-22Mechanical properties：

Alloy plate size	Welding method	Test temperature/℃	σb/MPa	σp0.2/MPa	δ/%
Sheet thickness3.2mm	GTAW	room temperature538	745 543	119 274	30 23
Medium plate thickness6.4mm	GTAW	room temperature538	800 610	386 245	60 51
	GMAW(Short arcs)	room temperature538	767 586	396 265	43 46
Medium plate thickness12.7mm	GTAW	room temperature538 760	788 590 489	451 312 269	47 52 30
	GMAW(Short arcs)	room temperature538 760	749 562 437	435 308 266	38 38 25
	GMAW(Arc scattering)	room temperature538 760	756 555 470	461 321 282	37 33 27

Hastelloy C-22Alloy properties：

Corrosion resistance: The alloy has good corrosion resistance in acetic acid, 10% FeCl₃, formic acid, extracted phosphoric acid, and some concentrations of sulfuric acid. Stress corrosion at 20 . In 4%MgCl₂, Hastelloy C-22 alloy has good chloride stress corrosion resistance after one week of testing.

Test conditions	204℃	232℃	hardness
Solid solution	No cracking	No cracking	83HRB
20% cold worked	No cracking	No cracking	33HRC
50% cold worked	No cracking	No cracking	43HRC

Hastelloy C-22Uses of alloys：

HuaNickel Hastelloy C-22 is a relatively new corrosion-resistant alloy. It is mainly used in seawater, acetic acid, acetic anhydride, chlorination and hydrogen fluoride systems, pickling equipment for phosphoric acid and mixed acid production, plate heat exchangers, SO cooling towers and other applications to solve problems such as total corrosion, pitting corrosion, and crevice corrosion.

Hastelloy C-22Process performance：

Welding process: welding performance

HuaNickel Hastelloy C-22 alloy has good weldability, and can be welded by the common welding methods of the aforementioned high-nickel-chromium-molybdenum alloys, such as GTAW, GMAW, SMAW, etc.

Heat treatment: After cold and hot processing, the solution treatment process of HuaNickel  Hastelloy C-22 alloy is heated at 1120°C, heat preservation and then quenching.

Relevant standards：

SB 575/B 575、 SB 574/B 574 、B 472、SB 622/B 622、 SB 619/B 619

SB 626/B 626、SB 366/B 366 、SB 462/B 462 、SB 564/B 564 、SB 462/B 462