Comprehensive Guide to Nickel-Based Alloys: Hastelloy G30 (UNS N06030)
What is Hastelloy G30?
Hastelloy G-30 is designated as UNS N06030 or DIN 2.4603. It is a nickel-chromium-iron material with excellent resistance to phosphoric acid environments (wet process). Hastelloy G30 is a nickel-based high-temperature alloy composed of nickel, chromium, cobalt, tungsten and other elements, with a nickel content of about 37%. It also has some resistance to localized corrosion caused by chlorides, which can be a problem underneath deposits in evaporators used to concentrate phosphoric acid. In addition, G-30 alloy is less susceptible to chloride-induced stress corrosion cracking than stainless steel. Hastelloy G30 is a nickel-based alloy with a high chromium content. It is better than most other nickel- and iron-based alloys for mixed environments with commercial phosphoric acid and a variety of highly oxidizing acid media such as nitric/hydrochloric acid, nitric/hydrofluoric acid and sulfuric acid. The alloy has good corrosion resistance.
Hastelloy G-30 is widely used in phosphoric acid, sulfuric acid and nitric acid processing industries, nuclear pipelines, petrochemical and fertilizer industries. G30 alloy can prevent the formation of grain boundary precipitation in the heat affected zone of welding, so its welded products are suitable for various chemical processing projects. Hastelloy G-30 (UNS N06230) is an improved version of Ni-Cr-Fe-Mo-Cu alloy G-3. G-30 has a higher content of chromium, cobalt and tungsten, and its corrosion resistance is better than most other nickel-based and iron-based alloys in commercial phosphoric acid and complex environments containing highly oxidizing acids. The alloy can resist the formation of grain boundary precipitates in the heat affected zone, making it suitable for most chemical process applications under welding conditions.
Production process of Hastelloy G30 alloy
1. Hot rolling;
2. Hot extrusion.
G30 alloy has poor high temperature plasticity, a narrow hot forming temperature range, and a large deformation resistance. Therefore, the production of Hastelloy G30 alloy pipe mainly adopts hot extrusion. Hot deformation of the blank in the extrusion barrel is the key technology of hot extrusion forming and the bottleneck of G-30 alloy pipe production.
Types of Hastelloy Alloys
Hastelloy B-3 Nickel-molybdenum alloy has excellent corrosion resistance in reducing environment
Upgraded version of Hastelloy B-3: B-3 has excellent corrosion resistance to hydrochloric acid at any temperature and concentration
Hastelloy C-4: Good thermal stability, good toughness and corrosion resistance at 650-1040℃
Hastelloy C-22: Better uniform corrosion resistance and excellent local corrosion resistance than C-4 and C-276 in oxidizing media
Hastelloy C-276: Good oxidation resistance and moderate reductive corrosion resistance, excellent stress corrosion resistance
Hastelloy C-2000: The most comprehensive corrosion-resistant alloy with excellent uniform corrosion resistance in oxidizing and reducing environments
Hastelloy G-35: An upgraded product of G-30, with better corrosion resistance and thermal stability, and excellent performance in highly oxidizing mixed acid media with high chromium content such as phosphoric acid
Hastelloy X.: Combining the characteristics of high strength, oxidation resistance and easy processing, each of the above grades has its specific chemical composition, mechanical properties and advantages, so we cannot generalize the characteristics of Hastelloy.
Hastelloy is mainly divided into three series: B, C, and G, and is mainly used in iron-based CrNi or CrNiMo stainless steel, non-metallic materials and other highly corrosive media.
In order to improve the corrosion resistance and hot and cold processing performance of Hastelloy alloy, three major improvements have been made to Hastelloy alloy:
B series: B → B-3 (00ni70mo28) → B-3
C series: C → C-276 (00cr16mo16w4) → C-4 (00cr16mo16) → C-22 (00cr22mo13w3) → C-2000 (00cr20mo16)
G series: G → G-3 (00cr22ni48mo7cu) → G-30 (00cr30ni48mo7cu)
The most widely used materials are N06030 (B-3), N10276 (C-276), N06030 (C-22), N06455 (C-4) and N06030 (G-3)
