This article describes research at Los Alamos National Laboratory that is aimed at building a coupled experimental and computational methodology that supports the development of predictive damage capabilities by: (1) capturing real distributions of microstructural features from real material and implementing them as digitally generated microstructures in damage model development, and (2) distilling structure-property information to link microstructural details to damage evolution under a multitude of loading states.

The absence of standards and a common vocabulary are an obstacle when it comes to evaluating the structure of thermal spray coatings. However, proper sectioning and mounting of metallographic specimens helps ensure that the images obtained accurately reflect the coating structure and the information that can be derived from it.

New designs of precision cutters are optimizing sample preparation for greater efficiency, consistency, and precision. This article describes how three main factors impact the sample cutting process: blade speed, blade composition, and control of heat and cutting load.

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.

An advanced, patented probe sensor provides early detection of water infrastructure problems caused by corrosion and harsh atmospheric conditions. Designed to detect graphitization in active pipelines, it identifies areas at risk of major failures early on. By using indirect methods like GIS mapping, in-situ soil resistivity testing, and structure-to-soil potential measurements, high-risk zones can be pinpointed. Once these areas are identified, the probe assesses the severity and depth of graphitization, providing a comprehensive evaluation of the pipeline’s condition. This allows for the implementation of effective corrosion management strategies, including cathodic protection systems, to prevent critical failures. This article describes the sensor system and provides a case study of its use. The technology received the 2024 Engineering Materials Achievement Award from ASM International.

Many broken parts look similar at a glance, but examination of the failed part using advanced equipment and methods such as scanning electron microscopy (SEM) reveals much more about the origins of the failure. This article presents a case history involving SEM analysis of a trailer hitch fatigue failure.

The materials testing industry must follow market trends, keeping up with both increased use of nonmetallic materials in fields formerly dominated by metals, as well as new and challenging metal alloys. This article reviews some of the testing challenges involved with advanced materials.

A microscale fatigue testing technique for characterizing mechanical response and relating it to microstructure promises to improve fatigue life prediction for turbine engine components.

Identifying metallographic TSC artifacts, specifically in air plasma spray zirconia-based thermal barrier coatings.

Nitinol fatigue fracture surfaces generally exhibit similar features to most engineering alloys, including a flat fracture plane, ratchet marks, radial lines, beachmarks, and striations.

Temperature measurement, unvented cavities, loose powder, and direct contact of certain metals must be considered during process development for vacuum heat treatment of additively manufactured parts.

Development of new, radiation-tolerant materials that maintain the structural integrity and safety margins over the course of a nuclear power reactor’s service life requires the ability to predict degradation phenomena. Modern post-irradiation examination methods make use of specialized high-flux test reactors and dedicated characterization facilities to limit occupational exposure and prevent the spread of radioactive contamination. This article illustrates the use of these advanced techniques to characterize precipitates in neutron-irradiated Fe-Cr-Al alloys.

This article reports on the development of additive friction stir deposition techniques that use secondary feedstocks such as machine chips and damaged components to make in-field repairs at the point of need. The focus of the initial research was aluminum alloys. Preliminary studies show significant promise for the adaptation of these techniques to hard alloys including steel castings, wrought high strength steels, and titanium alloys.

Although the widespread use of titanium alloys is constrained by high costs, powder metallurgy techniques such as additive manufacturing (AM) represent an economical approach to fabricating titanium components. Various approaches to AM, along with examples of components made by different AM processes, are presented. The microstructures and mechanical properties of Ti-6Al-4V produced by AM are also discussed and compared with cast and wrought products. Finally, the economic advantages of AM compared to conventional processing are presented.

Development of wear-resistant hardfacing materials using powder metallurgy/hot isostatic pressing technology offers an alternative to today's cobalt-based materials and those that suffer delamination damage. Ongoing research and development at the Electric Power Research Institute (EPRI), detailed in this article, examines the application of wear-resistant hardfacing materials using the PM/HIP process. The hope is to eliminate weldability and residual stress challenges associated with some hardfacing alloys, as well as to provide a wider range of potential alloy solutions to reduce cobalt use and to address delamination issues with incumbent materials.

A recent metallographic and historical analysis of two parts from the Buenos Aires to Pacific Railroad railway looked at possible manufacturing techniques of the parts in question. The information collected is useful for comparison with techniques and materials used at that time as well as with current techniques. The analysis questioned whether the material itself has varied or evolved from the metallurgical point of view, and confirmed the quality of raw material used to construct the historic railway line.

This article provides an overview of cracking and fracture mechanisms in heritage gold, silver, low-tin bronze, and wrought iron alloys. Understanding these mechanisms can be important for restorers, and possibly for conservators and curators as well. Metallography is widely used (when sampling is permitted) for studying archaeometallurgical artifacts in detail. However, fracture surface examinations and analysis (i.e., fractography) can often provide even greater insight. Case studies demonstrate the benefits of employing fractographic analysis to study cracking and fracture mechanisms in heritage alloys.

Examining a failed part’s fracture surface is a great source of information as to why and how it failed.

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.

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.