Search Results for fractography

This article summarizes the more common analytical techniques for studying ancient metal artifacts, illustrated by case histories. There are two main classifications: noninvasive and invasive techniques. This distinction is of prime importance because some heritage objects may be too rare or valuable for invasive sampling, or there may be ethical objections to certain types of examination. Noninvasive examination of ancient metal artifacts is important, yet it cannot provide the detailed information obtainable from invasive techniques. This is especially true when artifacts contain “hidden” damage and there is also a need for accurate quantitative analyses.

Although stress corrosion cracking (SCC) accounts for just a fraction of all engineering failures, its prevention is a major problem, particularly in the aerospace industry. Recent archaeometallurgical studies show that stress corrosion cracking occurred in ancient metallic artifacts. This article describes investigations that revealed definite evidence for SCC in ancient silver and bronze alloys and a probable case of SCC in low-carat (13K) gold. Diagnostic methods included visual inspection, metallography, and fractography.

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.

The production and processing of advanced materials, namely metals and alloys, began in the Old World about 8000 years ago and developed over many millennia, providing a lasting legacy for modern civilizations. This article gives a brief overview of the production and processing of ancient bronzes and silver in the Old World, and also mentions post-processing problems including corrosion and embrittlement, owing to long-term burial before archaeological recovery.

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

Explore the latest information regarding ASM International’s global reach, audience demographics, and core initiatives shaping the future of the materials science and engineering community.

Difficulty in clearly and quantitatively answering questions concerning a component or product failure can lead to courtroom debates, arguments, and battles. The case studies in this article identify and describe technical procedures to assist with explaining complex situations and thereby assist in solving failure analysis problems and resolving legal disputes.

This article reports on a multifaceted testing and modeling approach to investigate the fatigue life of medical grade Nitinol to one billion cycles. The goal of a the research is to understand the mechanism of Nitinol ultra-high cycle fatigue and to eventually be able to predict when fracture will occur.

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

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: MS&T 2013 Lecturers Announced; 2013-2014 Student Board Members Announced; Jean Duval Educational Fund with ASM Foundation; Chapter News.

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.

In Germany, the Federal Institute for Materials Research and Testing (BAM) is addressing challenges in the implementation of additive manufacturing on the industrial landscape for safety-critical applications. This article provides an overview of BAM’s activities in additive manufacturing with a focus on safety (both for applications and the environment) and AM technology innovation for a wide range of materials and manufacturing locations.

Fasteners play a critical role in engineered structures as a method of nonpermanent joining for the aerospace, infrastructure, civil, automotive, energy generation/distribution, and many other industries. Fastener failures can lead to disastrous consequences and substantial financial losses. One of the most common fastener failure modes is fatigue crack initiation and growth. Inadequate design considerations, material problems, insufficient preload, loosening, and excessive loads can all contribute to fastener fatigue. A case study of steel screw failures highlights some of the critical manufacturing and design factors that affect fastener fatigue.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: The International Organization on Shape Memory and Superelastic Technologies (SMST) announces a graduate research fellowship; ASM President Sunniva Collins describes the benefits of participating in local ASM chapter activities; emerging professional Rachel Bethancourt recounts her experiences in navigating a workplace alongside experienced personnel.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: Burak Akyuz, president of the new ASM Failure Analysis Society, shares insights about the new organization; volunteer profile for James Boileau; Charles Kuehmann joins Tesla and SpaceX.

Characterizing ice and snow is important not only for building accurate climate models, but also for activities such as relating the mechanical properties of sea ice to its microstructure so that the interaction of ice with ships and structures can be better understood. This article describes the microstructural characterization of ice. Many microstructural characterization techniques that can be applied to other materials also can be used to examine ice.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: ASM introduces a new logo for the society; volunteer profile for Steven Ashlock; the ASM Medical Materials Databases introduces a new neurological module.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: 2012 ASM Awards Recipients and volunteer profile for Beth Armstrong, Oak Ridge National Laboratory.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: ASM affiliate societies announce new officers and and board members for 2020; ASM President Diana Essock describes diversity, equity, and inclusion initiatives by the society; Sarah M. Graham receives certficate of achievement in metallography from the ASM Education Department; professional profile for Melanie Buziak; recap of an emerging professionals session at the IMAT 2020 virtual event; photo gallery of highlights from IMAT sessions.