B2-B3

Hastelloy B-2 (UNS N10665）

Hastelloy B-3 (UNS N10675）

Summary

A corrosion-resistant solid-solution nickel-molybdenum alloy, Hastelloy B-2 exhibits excellent corrosion resistance in aggressive reducing media such as hydrochloric acid in a wide range of temperatures and concentrations, as well as in medium-concentrated sulphuric acid even with limited chloride contamination. Can also be used in acetic and phosphoric acids, and to a wide range of organic acids. The alloy has good resistance to chloride-induced stress corrosion cracking (SCC).

Hastelloy B-3 alloy is an additional member of the nickel-molybdenum family of alloys with excellent resistance to hydrochloric acid at all concentrations and temperatures. It also withstands sulfuric, acetic, formic and phosphoric acids, and other nonoxidizing media. B-3 alloy has a special chemistry designed to achieve a level of thermal stability greatly superior to that of its predecessors, e.g. HASTELLOY B-2 alloy. B-3 alloy has excellent resistance to pitting corrosion, to stress-corrosion cracking and to knife-line and heat-affected zone attack.

Standard
Product Forms

Pipe, tube, sheet, plate, round bar ，flanes, valve, and forging.

Pipe, tube, sheet, plate, round bar , flanes, valve, and forging.

Limiting Chemical Composition, %

	Min.	Max.		Min.	Max.		Min.	Max.
Ni	Remainder		Cu		0.5	C		0.02
Cr		1.0	Co		1.0	Si		0.1
Fe		2.0	Al			P		0.04
Mo	26.0	30.0	Ti			S		0.03
W			Mn		1.0	N

	Min.	Max.		Min.	Max.		Min.	Max.
Ni	65.0		Cu		0.2	C		0.01
Cr	1	3	Co		3	Si		0.1
Fe	1	3	Al		0.5	P		0.03
Mo	27	32	Ti		0.2	S		0.01
W		3	Mn		3	V		0.2

Physical
Constants

Density,g/cm3							9.2
Melting Range,℃							1330-1380

Melting Range,℃							9.22
Melting Range,℃							1330-1380

Typical
Mechanical
Properties

(Solution-treated)

Product forms	Yield strenth	Tensile strenth	Elongation	Brinell
				hardness
Plate Sheet	340	755	40	250
Rod Bar	325	745
Pipe Tube	340	755


Tensile Properties of Sheet (Limited data for 0.125" (3.2mm) bright annealed sheet


Test Temperature, ℃：Room
Tensile Strength, Mpa：860
Rp0.2 Yield Strength, Mpa: 420
Elongation in 51mm, %: 53.4

Microstructure

Hastelloy B-2 has a face-centered-cubic structure. The alloy's controlled chemistry with minimum iron and chromium content reduces the risk of embrittlement occurring during fabrication, as this retards precipitation of Ni4Mo phase in the temperature range 700-800 ℃.

Hastelloy B-3 also has a face-centered-cubic structure.

Characters

1. Controled chemistry with a minimum iron and chrlmium content to retard the formation of ordered β-phase Ni4Mo ;
2. Significant corrosion resistance to reducing environment;
3. Excellent resistance to medium-concentrated sulphuric acid and a number of non-oxidizing acids;
4. Good resistance to chloride-induced stress-corrosion cracking (SCC);
5. Good resistance to a wide range of organic acids.

1. Maintains excellent ductility during transient exposures to intermediate temperatures；
2. Excellent resistance to pitting and stress-corrosion cracking
3. Excellent resistance to knife-line and heat-affected zone attack；
4. Excellent resistance to acetic, formic and phosphoric acids and other non-oxidizing media
5. Resistance to hydrochloric acid at all concentrations and temperatures；
6. Thermal stability superior to alloy B-2.

Corrosion Resistance

The extremely low carbon and silicon content of Hastelloy B-2 reduces precipitation of carbides and other phases in the heat-affected zone of welds and ensures adequate corrosion resistance even in the welded condition. Hastelloy B-2 exhibits excellent corrosion resistance in aggressive reducing media such as hydrochloric acid in a wide range of temperatures and concentrations, as well as in medium-concentrated sulphuric acid even with limited chloride contamination. It can also be used in acetic and phosphoric acids. Optimum corrosion resistance can be obtained only if the material is in the correct metallurgical condition and exhibits a clean structure.

Applications

Hastelloy B-2 is used in a wide range of applications in the chemical process industry, especially for processes involving sulphuric, hydrochloric, phosphoric and acetic acid. B-2 is not recommended for use in the presence of ferric or cupric salts as these salts may cause rapid corrosion failure. Ferric or cupric salts may develop when hydrochloric acid comes in contact with iron or copper.

Hastelloy B-3 alloy is suitable for use in all applications previously requiring the use of Hastelloy B-2 alloy. Like B-2 alloy, B-3 is not recommended for use in the presence of ferric or cupric salts as these salts may cause rapid corrosion failure. Ferric or cupric salts may develop when hydrochloric acid comes in contact with iron or copper.

Shanghai Fengqu Superalloy Co., Ltd.　 Tel:+86-21-69155998 　
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Add：101#,Boxue Rd, Jiading District, Shanghai,China Zip：201801 　E-mail:Sales@superalloy.com.cn