This article briefly reviews the factors that influence the occurrence of intergranular (IG) fractures. Because the appearance of IG fractures is often very similar, the principal focus is placed on the various metallurgical or environmental factors that cause grain boundaries to become the preferred path of crack growth. The article describes in more detail some typical mechanisms that cause IG fracture. It discusses the causes and effects of IG brittle cracking, dimpled IG fracture, IG fatigue, hydrogen embrittlement, and IG stress-corrosion cracking. The article presents a case history on IG fracture of steam generator tubes, where a lowering of the operating temperature was proposed to reduce failures.

This article briefly reviews the various metallurgical or environmental factors that cause a weakening of the grain boundaries and, in turn, influence the occurrence of intergranular (IG) fractures. It discusses the mechanisms of IG fractures, including the dimpled IG fracture, the IG brittle fracture, and the IG fatigue fracture. The article describes some typical embrittlement mechanisms that cause the IG fracture of steels.

This article is an atlas of fractographs that helps in understanding the causes and mechanisms of fracture of one specific type of cemented carbide, tungsten carbide. It also assists in identifying and interpreting the morphology of fracture surfaces. The fractographs illustrate the brittle fracture, transgranular fracture, intergranular fracture, and crack propagation of the tungsten carbide.

This article is an atlas of fractographs that helps in understanding the causes and mechanisms of fracture of nickel alloys and in identifying and interpreting the morphology of fracture surfaces. The fractographs illustrate the fatigue crack, transgranular cleavage, intergranular fracture, grain boundaries, notch and fatigue precrack, dimpled rupture, and fatigue striations of these alloys.

As cast iron parts are extensively applied, fracture events will eventually take place. Consequently, it becomes essential to carry out failure analyses to identify the cause of fracture and to provide corrective actions that allow safe operation. This article presents a description of the main fracture modes and their characteristic fractographic features. It discusses the four principal fracture modes: dimple rupture (or fracture), cleavage, fatigue, and intergranular fracture. The article provides information on special cases of environmentally assisted fracture. It concludes with a description of fractographic analyses for identifying the direction of propagation of a crack.

This article is an atlas of fractographs that helps in understanding the causes and mechanisms of fracture of precipitation-hardening stainless steels and in identifying and interpreting the morphology of fracture surfaces. The fractographs illustrate the cup-and-cone tension-overload fracture, low-cycle and high-cycle fatigue fracture, fracture surface, brittle intergranular fracture, hydrogen embrittlement, and intergranular stress-corrosion cracking of stainless steel components of these steels. The components include high-pressure compressor parts, springs, deflector yokes of aircraft main landing gears, and aircraft engine mount beams.

This article describes the microstructure, properties, and performance of carburized steels, and elucidates the microstructural gradients associated with carbon and hardness gradients. It provides information on case depth measurement, the factors affecting case depth, and the formation and causes of microcracks. The article discusses the effects of alloying elements on hardenability, the effects of excessive retained austenite and massive carbides on fatigue resistance, the effects of residual stresses and internal oxidation on fatigue performance of carburized steels. In addition, the causes of intergranular fracture at austenite grain boundaries and their prevention methods are explored. The article also describes the major mechanisms of bending fatigue crack initiation in carburized steels.

This article discusses the visual and microscopic characteristics of fractures of cast alloys. These fractures include ductile rupture, transgranular brittle fracture, intergranular fracture, fatigue, and environmentally induced fracture. The article also describes the factors that affect fracture appearance.