Search Results for weld strength

Compared to traditional power plant materials, creep strength enhanced ferritic steels require new approaches to nondestructive examination and weld repair. The metallurgical complexity of these steels prompted EPRI to conduct research to define and/or improve the detection limits of ultrasonic testing techniques, explore novel electromagnetic techniques, evaluate the sensitivity and applicability of acoustic emission testing, and conduct studies on improved weld repair procedures.

This article describes how shielding gas composition, either argon or nitrogen, affects the hardness, tensile strength, and toughness of high-power, high-brightness laser welds made on various base materials, including A508 forging steel, 316L stainless steel, Inconel 690, and solution-annealed IN718.

Advanced instrumentation combined with effective test procedures gives manufacturers an edge in measuring and analyzing welds.

Automobile performance and passenger safety both rely on sound spot welds in advanced high-strength steels. A new, high-frequency ultrasonic matrix phased array probe performs nondestructive inspection of these welds, saving time and cost.

Typical vehicles contain more than 3000 spot welds, and failure parameters for these welds must be accurately predicted in crash simulations. A testing protocol developed at EWI for the purpose of creating spot weld failure parameters has been used since 2010 to establish these parameters for automotive manufacturers for a range of steel and aluminum stack-ups. Crash simulations in full-vehicle models show that the failure parameters created by this method are accurate for predicting the initiation of spot weld failure by comparing results with experimental data.

A new solid-state joining process for medical guidewire applications increases joint strength, provides superior bending properties, and does not require tertiary metals or ferrules. This process may be a superior method to create joints between dissimilar metals such as stainless steel and Nitinol.

This article describes research leading to the development of a new grade of low temperature bainitic steels, named Kinetically Activated Bainite (KAB) steels. with exceptionally rapid transformation kinetics at temperatures below 200°C. This entry won the Jacquet-Lucas Award for Best in Show at the 2015 International Metallographic Contest.

The 10th Liège Conference on Materials for Advanced Power Engineering was held in September 2014. This article presents conference highlights, including the current state of European materials research for advanced power engineering applications; European multinational programs in this area; and critical research topics including creep-fatigue, new alloy development, and materials developments for gas turbines.

A novel approach in the field of narrow gap laser welding produces superior weld joint quality, especially the configuration of weld toe, which has a positive effect on fatigue life.

Linear friction welding (LFW) is a solid-state process capable of joining noncircular parts by oscillating one part under load to create frictional heating. From joining railroad rails to producing strong aluminum-to-steel joints, recent advancements in LFW technology are reducing equipment costs and expanding potential uses.

A new high-strength steel developed for cold stamping addresses the challenges presented by materials traditionally used to manufacture electric vehicle components.

A new process called nanofunctionalization was successfully used to control the solidifying microstructure during additive manufacturing and produce crack-free 7000 and 6000 series aluminum alloys for the first time.

A new welding process known as hybrid induction arc welding (HIAW) or high deposition arc welding (HiDep) uses a hybrid approach to reduce—or even eliminate—weld distortion and greatly increase productivity. Operating directly in front of the arc welding torch, a portable induction coil heats the surfaces of the weld to, or near, the melting point. Heat generated by the welding arc is primarily used to melt the welding wire. This novel process operates at speeds two to four times faster than conventional arc welding and substantially reduces weld distortion.

This article describes the investigation conducted by the National Transportation Safety Board following an explosion triggered by a natural gas pipeline rupture. In addition to determining the likely cause of the rupture, the NTSB issued safety recommendations calling for hydrostatic pressure testing of similar gas lines and making them more amenable to inline inspection methods.

Mechanical spot-joining methods such as self-pierce riveting (SPR) enable the use of different material combinations in vehicle design. The SPR technique provides a robust joint that often outperforms clinching and spot welding under both static and fatigue conditions, while providing fast cycle times and zero waste.

Beyond weight savings, aluminum products offer corrosion resistance, weldability, and ease of maintenance for a wide range of marine vessels. Aluminum was recognized as a promising material for marine construction from the early days of the industry. The development of 5xxx alloys and large production capacity made aluminum use more technically and economically possible beginning in the 1950s. The variety of aluminum vessels ranges from small fishing boats and fast ferry catamarans to cruise ships and military vessels. All benefit from aluminum's relatively light weight, low maintenance costs, and easy repairability. Other benefits of using aluminum in marine applications include formability, corrosion resistance, and availability in various product forms.

Two case studies highlight the strengths and weaknesses between traditional metallurgical techniques and 3D micro-computed tomography, as well as the interplay between the two.

Flash processing, a new heat treatment for steels based on the concept of rapid thermal cycling, has been shown to achieve new levels of strength and ductility. This article describes the process, its effects on microstructure, and the phase transformations involved. It also discusses current and potential future applications.

This article identifies several factors that are not fully addressed in most fracture toughness test standards and explains how they may influence calculated values obtained from ferritic steels. Of particular consequence are test temperatures within the ductile-to-brittle transition regime and test specimen geometries when measuring the toughness of weld metal and heat-affected zones.

Orion’s Exploration Flight Test 1 vehicle used four additively manufactured vent assemblies to equalize pressure between unpressurized portions of the spacecraft and the external environment.