Our alloy experts will be presenting their technical papers at AMPP Annual Conference + Expo in New Orleans, Louisiana, March 3rd-7th, 2024. Join our alloy experts as they present their technical papers during the conference.
Tuesday March 5, 2024
starting at 11:00am
Presenter: Ling Chen
Authors: Ling Chen, Jeremy L. Caron, Vinay Deodeshmukh
Presentation Title: Corrosion Performance of Welded N10675 Alloy Prepared by GMAW,GTAW And SMAW
Presentation Details: The corrosion performance of N10675 alloy weldments prepared by GMAW (Gas Metal Arc Welding/MIG Welding), GTAW (Gas Tungsten Arc Welding/TIG Welding) and SMAW (Shielded Metal Arc Welding/Stick Welding) were evaluated. Welded plates (0.5” thick) and sheets (0.125” thick) were investigated in this work. Overall corrosion loss rates in boiling 20%HCl acid were similar, irrespective of the type of welding method. Intergranular penetration attack occurred at the heat-affected-zones (HAZ) of all three as-welded 0.5” thick plates and was more pronounced near the weld root. GMAW samples exhibited a slightly deeper corrosion penetration attack compared to GTAW and SMAW samples. While the corrosion rates of 0.5” thick weld samples postweld heat treated (PWHT) at 1066°C were slightly higher than as-welded samples for each welding method, PWHT was shown to significantly lessen the depth of intergranular corrosion attack in the HAZ. In contrast, the impact of PWHT on the corrosion performance of the thin-gauge sheet welds was negligible. In addition, no stress-corrosion cracking (SCC) occurred on 0.125” thick U-bend welded sheets prepared by GMAW, GTAW and SMAW.
Thursday March 7, 2024
starting at 11:00am
Presenter: Ling Chen
Authors: Ling Chen, Michael G. Fahrmann, Jeremy L. Caron, Vinay Deodeshmukh
Presentation Title: Mechanical Properties and Thermal Stability of Metal Dusting Resistant Nickel-Base Alloy N06235
Presentation Details: Nickel-base N06235 alloy is a solid-solution strengthened Ni-Cr-Mo-Cu alloy that was developed to resist metal dusting corrosion attack in high temperature structural applications involving carbonaceous and other high temperature corrosive environments, particularly in syngas production and processing environments. Improved metal dusting resistance was achieved by significant additions of copper and high amounts chromium to inhibit carbon deposition, ingress, and coke formation as previously reported. The high temperature creep-rupture and tensile strength of the wrought alloy and its weldments were investigated in this paper. Weld samples produced by Gas Metal Arc Welding (GMAW) and Gas Tungsten Arc Welding (GTAW), exhibit tensile and creep-rupture strength similar to that of wrought alloy in the temperature range from 538 to 10930°C(1000 to 20000°F). In addition, the retained room and elevated temperature tensile properties of the wrought base metal after 4000-hour long-term aging at temperatures from 649 to 871°C (1200 to 16000°F) are reported.
Thursday March 7, 2024
starting at 10:10am
Presenter: Bingtao Li
Authors: Bingtao Li, Vinay Deodeshmukh, Lee M. Pike
Presentation Title: Oxidation Resistant Behaviors of Commercial High-Temperature Alloys in the Atmospheres Containing Water Vapor
Presentation Details:Water vapor has significant effects on high temperature oxidation behaviors of high temperature alloys, especially on chromia-forming alloys due to oxidative evaporation of chromia scale. The objectives of this work are to study high temperature oxidation behaviors of commercial high temperature alloys, including seven chromia-formers, such as N06230, R30188, N08120, N06002, N06625, N06617, S34700, and three alumina-formers, such as N07214, NiCoCrMoAl, NiFeCrAl, at the temperatures from 760 to 1093°C (1400 to 2000°F) for up to one year exposure in the air atmospheres containing (5-30)% water vapor. The effects of water vapor content, temperature, heating/cooling condition, and alloy composition were analyzed from the results of metal loss and internal oxidation penetration, along with comparison with their oxidation behaviors tested in air without water vapor addition. The study shows, in general, water vapor could accelerate oxidation attack, and higher water vapor contents could cause more oxidation attack. However, high temperature oxidation behaviors of high temperature alloys will depend on multiple factors that need to be considered, especially when comparing oxidation results generated under different testing conditions.