Search Results for weld hardness

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.

Metallographic examination and optical emission spectroscopy shed light on the origin of a lampshade found in the aftermath of Hurricane Katrina. The steels used for the ring and wire in the frame are typical of those made prior to WWII and the fabrication processes appear to be of a similar timeframe. Tassels on the lampshade were determined to be a more recent alteration and the fabric was found to be cow skin parchment based on DNA testing.

Integrated computational materials engineering (ICME) is a relatively new discipline that shows great promise for reducing the cost and time required to design and deploy new materials, manufacturing technologies, and products. This article introduces an ICME implementation framework for product development using modeling of a friction stir welding process as an example.

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.

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.

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.

Through a series of case studies, the benefits of micro x-ray fluorescence (XRF) over traditional XRF are demonstrated in the power generation industry for informing weld procedures, identifying root cause, and providing materials or component specifications.

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.

In order to expand the choice of materials available for use in additive manufacturing, parameters that consider welding metallurgy, laser powder interaction, and post processing must be developed. This article describes the outcomes of process development for a steel and stainless steel alloy that are not standard materials for laser powder bed fusion equipment.

Laser cladding applies thin deposits of hard or corrosion-resistant materials to surfaces susceptible to damage. This article discusses the advantages and drawbacks of laser cladding in comparison to thermal spraying.

A new fusion cladding process that uses high-intensity arc lamps can produce pinhole free, smooth, uniform coatings as thick as 15 mm from various feedstock materials. This article briefly describes the process and the corrosion, wear, and high-temperature behavior of fusion claddings designed for oil and gas pipelines and related components.

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.

In recognition of ASM International's 100-year anniversary , AM&P highlights historic events and technological advancements that occurred over the course of those years. This issue extends the timeline from 1924 to 1933, which includes the invention of 18-8 (type 304) stainless steel, the development of the Vickers hardness test, the debut of tungsten carbide cutting tools, and the first all-metal single-wing aircraft to transport mail.

Cold spray was primarily developed for use in applications that are extremely sensitive to high process temperatures. Due to this factor and its other unique capabilities, cold spray is becoming attractive as an enabling technology for 3D printing or additive manufacturing. Current work is focusing on reducing the spot size of cold spray systems to enable them to produce more intricate and highly finished shapes.

Advanced materials engineering is being used to solve component life cycle improvement challenges in extremely harsh working conditions. This article discusses examples from various industries where new materials and surface modifications are used to extend the useful life of engineering components and equipment.

Recent advances in high velocity oxygen fuel torches in the form of miniaturization, joining, automation, and digitization are increasing the application opportunities for this thermal spray coating technology.

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.

This article focuses on five common reasons for distortion and cracking during heat treatment and recommended remediations: (1) Nonuniform and uncontrollable heat transfer during heating and cooling; (2) Structural changes during phase transformation; (3) Residual stresses in the part that occur due to forming, welding, or machining before heat treatment; (4) Macro or micro steel structure; and (5) Fixturing and loading errors.

This guide outlines recent advances in the various methods of laser technology and appropriate manufacturing applications. Each process has unique requirements and matching the laser source to the project is essential for developing a robust solution.

A digital refractometer gives more accurate quench concentration readings thereby reducing maintenance, increasing productivity, and ensuring desired metallurgical properties.