Maraging steel

About: Maraging steel is a research topic. Over the lifetime, 1728 publications have been published within this topic receiving 19886 citations. The topic is also known as: martensitic ageing steel.

The rolling texture of 18% Ni-350 maraging steel

Abstract: Texture development in hot rolled sheet and hot forged tube of 18%Ni- 350 maraging steel has been studied after various degrees of cold deformation and flow turning, respectively. Hot rolled sheet exhibited considerable mechanical anisotropy. Weak texture development was observed following flow turning compared to cold deformation. Above 80% deformation, an increase in work hardening was accompanied by an increase in the orientation density of the texture component (001 )[110]. Deformation of 97% leads to the development of the texture component (111)[110], with the highest orientation density 10.3 times random and a constant orientation density of 9 times random along (φ1 at ϕ = 55° and φ2 = 45°. This texture was correlated with the appearance of shear bands in the microstructure.

Observations of decomposition of martensite during heat treatment of steels using atom probe tomography

Abstract: The decomposition of martensite during tempering or ageing is an important phenomenon as it leads to changes in the mechanical properties. These changes could take place during both steel manufacturing or in-service. Thus, their understanding is required to predict the material performance. Recent advances in the development of local electrode atom probes has led to a significant increase in the analysed volume of material (up to 100 millions of atoms) and at the same time reduced the acquisition times. This allows improvement in data statistics when investigating fine nanoscale features, such as solute segregation, clustering and ultrafine precipitation. Selected results of atom probe studies on the decomposition of martensite from bake hardening of a pre-strained Transformation Induced Plasticity (TRIP) steel and ageing of FeNiTiMnAl maraging steel are presented.

MECHANICAL PROPERTIES OF ULTRA-HIGH-STRENGTH 18Ni COBALT-FREE MARAGING STEEL

Abstract: The influence of heat treatment on the microstructure and mechanical properties of a 2000 MPa grade Co-free 18Ni maraging steel has been investigated, and the strengthening and toughening mechanisms were discussed. The experimental results show that the hardness of the steel in solution condition is independent of both the solution temperature and the time. A combination of high strength and good toughness can be reached under the peak-aged condition, where the ultimate strength is over 2100 MPa, and the elongation and KIC are 9% and 70 MPa· m1/2, respectively. The TEM observation revealed that a great deal of nanometer size precipitates, such as Ni3(Mo, Ti), is distributed in a high density dislocation matrix of the steel treated with peak-aged condition, which realizes a better match of strength and toughness. The precipitation strengthening in the present steel obeys the modified Orowan mechanism.

Method for evaluating yield strength of laser weldments of maraging steels using hardness test

Abstract: This paper describes a new method for predicting fracture location, joint efficiency and yield strength of laser weldments of Fe–Cr–Ni–Mo–Ti–Cu stainless maraging steel and 18 Ni maraging steel using hardness distribution analysis and incorporating Tabor’s relationship between hardness and yield strength for metallic materials. Fracture location of weldment can be determined by a parameter LF, hardness ratio of heat affected zone (HAZ) to fusion zone (FZ) or HAZ to parent material zone (PMZ). Whether or not the yield strength of weldments is improved as compared with as received material via various post-weld heat treatments can be estimated qualitatively by a parameter YI, hardness ratio of predicted fracture location to as received parent material. The yield strength of weldments is well predicted in as weld and heat treated conditions using hardness modeling, the maximum errors of predicted yield strength are 3·3 and 2·5% of measured yield strength for weldments of Fe–Cr–Ni–Mo–Ti–Cu and 18Ni maraging s...