Inconel 690 is a single-phase austenitic nickel-based corrosion-resistant alloy with excellent comprehensive properties. It has better corrosion resistance and cracking resistance than 304 stainless steel, Inconel 600, and Incoloy 800 in chloride-containing solutions and sodium hydroxide solutions. It also has high strength, good metallurgical stability and workability. Especially in various high-temperature solutions, Inconel 690 has a low corrosion rate, showing excellent resistance to intergranular corrosion and stress corrosion cracking.
Inconel 690 nickel-based alloy has been widely used in surfacing and welding of key parts of PWR nuclear power plant equipment due to its excellent high temperature resistance and corrosion resistance, as well as the high welding quality of Alloy 690 welding wire and the ideal weld purity. Practical applications such as reactor pressure vessel and steam generator inlet and outlet pipe pre-stacking edge and butt welding seam with safety end, steam generator and waste heat exhaust heat exchanger tube sheet overlay welding, etc.
When using Inconel 690 nickel-based welding wire for welding, different welding processes are required due to the different structures and welding conditions of different welding parts:
● Take over the isolation layer welding, because of its strict requirements on the room temperature and high temperature strength of the weld, it is necessary to adopt an automatic TIG surfacing process that not only meets the strength requirements but also has a higher efficiency.
● Steam generator and waste heat exhaust heat exchanger tube sheet surfacing welding, the welding workload is large, and the hot wire TIG surfacing process with higher welding efficiency is required.
● The butt joint of the dissimilar steel with the safety end, in order to fix the welding station of the suitable connection and the safety end, while ensuring the welding quality of the narrow gap weld of the dissimilar steel, the design adopts the pulsed all-position TIG welding process.
● When there is a small defect in the weld that needs to be removed for welding rework, manual TIG welding is used after the removal of the small defect.
● Inconel 690 nickel-based welding wire is welded by different TIG welding processes, and the room temperature and high temperature tensile strength of the deposited metal are quite different due to different welding processes. Cold wire DC TIG welding has the highest strength of deposited metal; cold wire pulse TIG welding has the second highest strength of deposited metal; hot wire TIG welding has the lowest strength of deposited metal.
● The strength of the deposited metal of hot wire TIG welding and cold wire pulse TIG welding does not change significantly with the decrease of heat input, while the strength of the deposited metal of cold wire DC TIG welding increases significantly with the decrease of heat input.
● The difference in strength of deposited metal under different welding processes and different welding heat inputs is presumed to be due to the different effects of different welding processes and different welding heat inputs on the precipitation of hard phases in the grain boundaries of the deposited metal, but the in-depth reasons need to be further Research confirmed.
Wudenalloyhas focused on the production and manufacture of nickel alloys for more than ten years. We are a principal worldwide supplier of corrosion-resistant alloy and other superalloy metals. We have a professional technical team and after-sales service, so we can offer high -quality Hastelloy, Incoloy, Inconel, Monel, Duplex Stainless Steel and other alloy material. These materials are available in wire, bar, sheet&plate, pipe&tube, flange, forging, and other forms to meet the needs of our customers.
Ask a quote for the latest price and one of our team members will respond as soon as possible. Fields marked with * are required.