Liquid Metal Processing & Casting Conference (LMPC 2022): Defects During Processing I
Program Organizers: Matthew Krane, Purdue University; Mark Ward, University of Birmingham; Abdellah Kharicha, Cdlab Mhd Montauniversitaet

Tuesday 3:30 PM
September 20, 2022
Room: Grand Ballroom
Location: Bellevue Hotel

Session Chair: Kyle Fezi, Fort Wayne Metals

3:30 PM
Elimination of Defects in Titanium Using PAM-CHR Melting: Neill McDonald¹; Emiliane Doridot²; Stephane Hans²; Jerome Delfosse³; Lea Decultot⁴; Jean-Pierre Bellot⁴; Alain Jardy⁴; ¹MetaFensch; ²Aubert & Duval; ³Safran Tech; ⁴Université de Lorraine - Institut Jean Lamour
     Titanium is defined as a critical raw material by the European Union and other entities due to its industrial importance as well as a current reliance on importations. Recycling titanium scraps can lead to strategic, economic and environmental gains. One of the challenges, especially for applications such as aerospace, is the need to detect and remove critical defects such as inclusions. In titanium scrap these are generally classified as high-density (HDI) such as tungsten carbide tooling or low-density (LDI) such as oxides or nitrides.A pilot-scale plasma-arc melter (PAM) with a multi-zone cold hearth crucible has been used to study these defects. First, numerical simulation was used to determine the residence time of the liquid flow. Melts were then deliberately seeded with HDI and LDI with analysis of the skull and ingot using various techniques in order to study the behavior of these defects.

3:55 PM
Effect of Solidification Condition on Sulfide Morphology in Free Machining Austenitic Stainless Steel: Keiji Azuma¹; Yoshinori Sumi¹; ¹Daido Steel Co., Ltd.
    In the production of free-machining austenitic stainless steels with dispersed sulfide by continuous casting or ingot casting, sulfide morphologies vary depending on the position inside products due to the partial difference of solidification condition. In the final solidification zone at the center of slab or ingot, an increase of concentration of solute in the liquid phase causes coarsening of the sulfides. Coarse sulfides increase susceptibility to cracking during rolling and cause defects during machining, so it is necessary to control the morphology of sulfides. The generation of coarse sulfides is supposed to be caused by macro-scale phenomena during casting, but detailed mechanism has not been clarified. In this study, laboratory scale model samples of Fe-0.075C-0.2Si-1.85Mn-0.3S-8Ni-18.8Cr-0.25Mo(mass%) stainless steel simulating the solidification conditions of the center of slab or large ingot in mass production process were prepared and the effect of solidification conditions on the sulfide morphology was investigated.

4:20 PM
Segregation of Impurities in Metallic Lithium Through Melt Settling: Christian Bustillos¹; Mihail Bora¹; Luke Thornley¹; Gabriella King¹; James Cahill¹; Joshua Kuntz¹; Wyatt Du Frane¹; ¹Lawrence Livermore National Laboratory
    Metallic lithium (Li) plays a pivotal role within the energy sector. Li metal has drawn interest for use as anodes in batteries, a precursor for the preparation of many other Li compounds that are critical to renewable energy, and as a liquid coolant in advanced nuclear reactors. Li readily reacts with moisture in air leading to the formation of corrosive oxygen compounds, which can be detrimental to its chemical properties. Methods for removal of these impurities are needed to preserve Li resources. We present the segregation of LiOH and other impurities from Li through column melt settling after a thermal treatment, decreasing oxygen content to < 200 ppm. Karl Fischer Titrations, Archimedes density measurements, and X-Ray Computed Tomography proved useful in quantifying and mapping the LiOH in Li after a thermal treatment. Incorporation of induction heating expedited this purification process while yielding similar performance.

4:45 PM
Identifying Borides Inclusion in Aluminum Melt Using EDXRF for Small Spot Analysis: Hussain Al Halwachi¹; ¹Aluminium Bahrain (Alba)
    Inclusion in aluminum products is usually analyzed and identified by using Scanning Electron Microscope (SEM) and Optical Metallurgical Microscope, in order to find out the source of inclusions and prevent the recurrence. In absence of SEM and Metallurgical Microscope, it is extremely difficult to identify the source of inclusion, which affect the quality of aluminum final products and lead to customer complaints. In this study, a new analytical method is developed using Energy Dispersive XRF (EDXRF) to support the investigation of inclusion’s sources. The developed method was able to identify one type of aluminum final product inclusion, which is titanium borides. The method is able to provide quantitate analysis successfully.