The influence of nitrogen (0 to 0.27 wtYo) on martensite formation in an experimental low-nickel stainless-steel alloy (Fe-17Cr-7Mn-4Ni) has been investigated. The alloys containing 0.1 wtYo or more nitrogen are fully austenitic at room temperature; those containing less nitrogen consist of a mixture of austenite, martensite and S-ferrite. The alloys containing less than 0.2 wtYo nitrogen are m...

In recent years, TRIP/TWIP steels have been the focus of great attention thanks due to their excellent tensile strength-ductility combination. The compression tests were performed at different temperatures from 25 to1000°C to study the mechanical behavior of advanced austenitic steel with 21% manganese plus bearing Ti. The results indicated that the plastic deformation is controlled by deformat...

The author have developed a new SCC test method that enables the super Kelvin force microscope (SKFM) and the Kelvin force microscope (KFM) observations. By using this test device, the crack tip deformation and surface potential distribution were observed on SUS310S stainless steel by SKFM and KFM. At the same time, the distribution of hydrogen was examined by the Ag decoration method with the ...

Deformation behavior and microstructure evolution of NiTiCu shape memory alloy (SMA), which possesses martensite phase at room temperature, were investigated based on a uniaxial compression test at the temperatures of 700~1000 ◦C and at the strain rates of 0.0005~0.5 s−1. The constitutive equation of NiTiCu SMA was established in order to describe the flow characteristic of NiTiCu SMA, which is...

The stress corrosion cracking (SCC) of stainless steel is one of the biggest problems for maintaining atomic power and chemical plants. However the mechanism has not been solved because of difficulty in observing hydrogen movement. In order to solve this problem, the author has developed a new SCC test method that enables the super Kelvin force microscope (SKFM) and the Kelvin force microscope ...

Recently, with the requirement of lighter weight and more safety for a design of automobile, energy absorption capability of structural materials has become important. TRIP (Transformation-induced Plasticity) steel is expected to apply to safety members because of excellent energy absorption capability and ductility. Past studies proved that such excellent characteristics in TRIP steel are domi...

Related Articles High cyclic stability of the elastocaloric effect in sputtered TiNiCu shape memory films Appl. Phys. Lett. 101, 091903 (2012) Deformation induced martensite in NiTi and its shape memory effects generated by low temperature laser shock peening J. Appl. Phys. 112, 033515 (2012) Martensitic transformation and magnetic domains in Mn50Ni40Sn10 studied by in-situ transmission electro...

Ti-Nb-based Gum Metals exhibit extraordinary superelasticity with ultralow elastic modulus, superior strength and ductility, and a peculiar dislocation-free deformation behavior, most of which challenge existing theories of crystal strength. Additionally, this kind of alloys actually displays even more anomalous mechanical properties, such as the non-linear superelastic behavior, accompanied by...

Plastic deformations, such as those obtained by shot peening on specimen surface, are an efficient way to improve the mechanical behavior of metals. Generally, scanning electron microscopy (SEM) and electron backscattered diffraction (EBSD) are commonly used to observe the complex microstructural evolutions, such as grain refinement and phase transformation, induced by the surface treatment. In...

Shape memory alloys are typical temperature-sensitive metallic functional materials due to superelasticity and shape recovery characteristics. The conventional shape memory effect involves the formation and deformation of thermally induced martensite and its reverse transformation. The shape recovery process usually takes place over a temperature range, showing relatively low temperature-sensit...