Joining of Advanced and Specialty Materials (JASM XIII): Welding Technologies and Applications
Sponsored by: MS&T Organization
Program Organizers: Judith Schneider, Mississippi State University; Norman Zhou, Univ. of Waterloo; Leijun Li, Utah State University; Mathieu Brochu, McGill University; Boian Alexandrov, The Ohio State University; Michael Halbig, U.S. Army Research Laboratory; Akio Hirose, Osaka University; Sammy Tin, Illinois Institute of Technology
Thursday 8:00 AM
October 20, 2011
Room: E161B
Location: Greater Columbus Convention Center
Session Chair: Judy Schneider, Mississippi State University; Mike Halbig, NASA Glenn Research Center
8:00 AM Invited
Overview of Recent Developments in Laser Welding: Rosa Miranda1; 1FCT-UNL
Laser welding has significantly evolved since the 70´s with increasing applications in a wide range of industrial sectors.This presentation aims to provide an overview of recent developments in laser welding technology, focusing on high power fiber lasers applications, namely for pipeline welding and additive manufacturing.
8:20 AM Cancelled
Effects of Welding Positions on Droplet Transfer in CO2 Laser-MAG Hybrid Welding: Jiecai Feng1; Liqun Li1; Chunjin Hang1; Yanbin Chen1; Hao Qi1; 1State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology.
All-position welding is widely used in many industries such as the pipeline construction, the automobile factory and the shipyard. In this study, the variations of the behavior of the droplet transfer in the typical welding positions included the flat position, the vertical position and the horizontal position have been studied by high speed video photography during CO2 laser- MAG hybrid welding of 16 mm thickness E36 steel plates. The result indicates that the behavior of the droplet transfer noted by the frequency, the diameter and the deposition in weld pool have been found to vary significantly with different welding positions. Furthermore, by analyzing the arc characteristics, the MAG welding current and arc voltage waveform and the behavior of the droplet transfer, the effects of the welding positions on the weld morphology and the welding stability was investigated in details.
8:40 AM Student
Prediction of Concentration Profiles in a Diffusion Joint: Esfakur Rahman1; Matthew Cavalli1; 1University of North Dakota
Concentration dependency of diffusivity in a multi-component diffusion system makes it complicated to predict the concentration profiles of diffusing species. This so called chemical diffusivity is expressed as a function of thermodynamic and kinetic data. DICTRA software can calculate the concentration profiles using appropriate mobility and thermodynamic data. It can also optimize the diffusivity data using experimental diffusivity data and store as mobility data which is a linear function of temperature. In this work, diffusion bonding of Ni and Fe using Al and Cu interlayers are reported. The mobility parameters of Ni- and Fe-(Cu or Al) binary systems are optimized using DICTRA/Thermocalc software. The concentration profiles of the diffusion couple are calculated using DICTRA/Thermocalc software and compared with experimental profiles. The microstructure and tensile strength of the diffusion joints are optimized.
9:00 AM Cancelled
Proper Welding Procedure to Sleeve Repair Internally Coated Fusion Bonded Epoxy (FBE) Water Lines: TARIQ ALGHAMDI1; Faisal Al-Abbas1; Yagoub Al-Nassar2; 1Saudi Aramco; 2King Fahd University of Petroleum and Minerals
The main purpose of this work is to develop an appropriate welding procedure for the installation of full encirclement repair sleeves on in-service, internally coated water lines. This procedure can be effectively used to sleeve repair internally coated Fusion Bonded Epoxy (FBE) water line with no harm on the internal coating. Any possible damage of FBE can lead to frequent leaks. Prevention of coating damage will increase the reliability of the supply/injection water system. The cost saving will be observed in increasing the remaining life of the sleeved girth welds and defective trunk lines. Multiple weld passes were applied to weld sleeve on in-service API 5LX60 pipelines of 12” diameter X 0.375” thickness. This experiment is performed on coated test spools with internal pressure of 185 psig and raw water temperature of 180ºF. From the actual observation of all cases performed, a specific and safe sleeve repair procedure is addressed.
9:20 AM Student
Use of Scrap Tire Derived Geomaterials in the Geotechnical Construction: Pranjal Barman1; 1Indian Institute of Technology, Guwahati
The problem associated with waste tire disposal can be mitigated by bulk utilisation of scarp tires in the field of geotechnical engineering. This paper discusses the various applications of tire chips as geotechnical construction material. Scrap tire derived materials have been emerged as a suitable and alternative geomaterials worldwide, since they provide cost-effective solutions to many practical problems. They have light weight, high vibration-absorption, high elastic compressibility, high hydraulic conductivity, and temperature-isolation potential. New techniques have emerged to utilize these advantageous characteristics for practical purposes. Mainly, two types of scrapped tire materials are used for civil engineering applications: with and without shredding or cutting into small pieces. The shredded tires can be used with or without mixing with soil because they have advantageous characteristics like those described above.
9:40 AM Break
10:00 AM Invited
A Manufacturing Strategy for the Assembly of Bi-Metallic Honeycomb Based Hybrid Materials Systems: Jerry Gould1; George Ritter1; 1Edison Welding Institute
New generations of technology evolution, whether in space, defense, or energy production are demanding materials systems combining high operating temperatures, improved mechanical integrity, and low densities. Operating temperatures for such applications can be as high as 1000°C. Such demands are increasingly driving the use of multi-materials solutions. This paper reports on a recent effort to integrate a combined metallic-ceramic-polymeric solution for such an application. The solution here involved a core bi-metallic honeycomb fabricated from refractory metal and titanium constituents. This paper will focus on the joining methods used for demonstrator component construction. Key to this construction was a bi-metallic joint made by resistance mash seam welding (RMSeW). Actual core build-ups were then done by resistance spot welding (RSW), and face sheet attachments were done by two independent brazing operations. Descriptions of the joining processes themselves will be provided, along with the metallographic and mechanical properties results from the joints produced.
10:40 AM
Formation Process of Intermetallic Compounds during Reactive TLP Bonding between Mg Alloy and Steel: Masaki Koba1; Toshio Araki1; Shoichi Nambu1; Junya Inoue1; Toshihiko Koseki1; 1The University of Tokyo
High bonding strength has been achieved at Mg alloy/steel interface by intentionally forming a thin and uniform intermetallic layer through the application of a new bonding process “Reactive Transient Liquid Phase’’ (RTLP) with Ag and Zn insertion. In this study, hot-dip experiment was conducted to clarify the formation process of the intermetallic compounds using Mg-Ag and Mg-Zn eutectic liquid with controlled Al concentration. IF steel sample was dipped into the eutectic liquid and the formation of intermetallic compounds was investigated at the steel surface by SEM-EBSP after various holding time. It was demonstrated that there existed two stages in the growth process of intermetallic compounds and that the growth at the second stage was faster than that at the first stage. In addition, it was found that the microstructure of intermetallic compounds became finer as the Al concentration in the eutectic liquid increased.
11:00 AM
Reactivity of the Faying Surface in Al-Mg2Si Metal Matrix Composite/Magnesium Alloy Bonds: Mehdi Mazar Atabaki1; Andrew Mullis1; 1The Leeds University
A model of dissolution and isothermal solidification during low temperature-partial transient liquid phase bonding process of Al/Mg2Si metal matrix composite to AZ91D joints using Al interlayer is presented. The model combined thermodynamic calculation and diffusion analysis. It was found that the lower temperature gradient resulted in increase of isothermal solidification. It is showed that kinetics of the bonding process significantly accelerated in presence of reinforcement (Mg2Si). This acceleration is attributed to the increased solute diffusivity through grain boundaries of the metal matrix composite. The numerical model estimates the fraction of wafer layer, formed at the surface of the substrates. Results suggest that Si and Mg contained in the interlayer favors the partial disruption of the aluminium oxide film, making easier the bonding process. However, the diffusion of Mg and its component to the grain boundary of the Al metal matrix composite was the main controlling factor in the bonding process.
11:20 AM
A Characteristic of HAZ of Mg Rolled Sheet on TIG Welding: Mokyoung Lee1; Norman Zhou2; 1RIST; 2University of Waterloo
Mg alloy sheet is being used many industrial fields such as automobiles, electronics, healthcare & leisure instrument, etc. To build light structure with Mg alloy, the joining of its parts is essential. TIG welding is in general for welding of nonferrous metal such as Al, Ti and Mg with high quality but low cost. But the joining of Mg alloy is difficult even though in TIG, because it is easily oxidized and evaporated under 1000℃. In this study, the weldability and the performance of weld was evaluated on TIG welding of rolled AZ31 Mg alloy sheet. The β-MgAl particle was formed in grains of weld metal and HAZ. Also the grain of HAZ was not uniform. But it was dissolved by heat treatment. As a result, the fatigue life of TIG welded AZ31 magnesium alloy was improved from 30MPa to 60MPa.
11:40 AM
Geometrical Modulations of Alloy Phases in Steel Microstructures by Using Spatial Welding: Soshu Kirihara1; Satoko Tasaki1; Yasunori Uehara1; Yousuke Itakura1; 1Osaka University
Geometric structures with periodic arrangements of steel phases with higher or lower carbon contents were fabricated and modulated to control heat and stress flows through the computer aided design, manufacturing and evaluation. Artificial dislocations of point and plane defects were introduced to realize energy localizations in the heat and stress flows. Spatial micro welding is a novel freeform fabrication process for metal or alloy components. A tungsten inert gas welding machine is controlled by utilizing computer aided design and manufacturing processes. Various steel wires with higher and lower carbon contents were fed automatically under a micro arc torch to form tiny beads through mixing and synthesizing reactions. These molten beads are joined continuously to build near-net-shape components with structural and compositional distributions. Thermal and mechanical properties measured by a thermo graph camera and a tensile testing machine were compared with simulated ones obtained by a finite difference time domain method.