The phase transitions in selective laser-melted 18-NI (300-grade) maraging steel

Abstract

Dilatometric studies in 18-Ni steel components fabricated by selective laser melting technique were carried out to determine the influence of heating rate on transitions occurring during the heating cycle. SLM components have been examined in controlled heating and cooling cycles. For analysis, heating of the analysed materials was carried out at heating rates of 10, 15, 20, 30 and 60 °C min −1 . During the heating process, two solid-state reactions were identified-i.e. precipitation of intermetallic phases and the reversion of martensite to austenite. A simplified procedure based on the Kissinger equation was used to determine the activation energy of individual reactions. For precipitation of intermetallic phases, the activation energy was estimated 301 kJ mol −1 , while the martensite to austenite reversion was determined at the activation energy 478 kJ mol −1 .Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Selective Laser Melting of 18NI-300 Maraging Steel

“…The third deviation occurred during the cooling cycle and corresponded to the martensitic transition, where M s and M f temperatures were 221 °C and 110 °C, respectively. Therefore, a single-phase microstructure characterized steel as martensite after cooling at room temperature [ 13 ].…”

“…Among machine part manufacturing technology, there is a common interest in additive manufacturing technology, which includes selective laser melting (SLM) [ 10 , 11 , 12 , 13 , 14 ]. In this method, a focused laser beam is used to spot powder beds and perform successive melting of the powder layer that bonds to current layers, which results in a 3D model.…”

Hot Deformation Treatment of Grain-Modified Mg–Li Alloy

“…In the presented work, the stability regions with a high power dissipation factor η , which relates to the optimal treatment states of DRX and DRV, were less productive when η < 50% because the generation of interfaces formulated by dislocation generation and simultaneous recovery took the energy. Conversely, the occurrence of cracking processes was characterized when η > 50%, because the energy conversion onto the surface was more effective [ 29 ].…”

“…Analysis of elements in the alloy was performed using an inductively coupled optical emission spectrometer with an inductively coupled plasma (ICP OES) OPTIMA 5300V, made by PerkinElmer (Waltham, MA, USA). The uniaxial hot compression experiments were completed using a DIL 805 A/D dilatometer delivered by TA Instruments (Zaventem, Belgium) [ 29 ], over a strain rate range of 0.01 s −1 to 1 s −1 and a temperature range of 250 °C to 400 °C, using a PtRh10–Pt thermocouple rod under an argon protective atmosphere to prevent sample oxidation. Before the compression experiments, the samples were heated up to the deformation temperature at a heating rate of 5 °C·s −1 and held isothermally for 5 min, before being compressed at a constant strain rate.…”

An Efficient Methodology towards Mechanical Characterization and Modelling of 18Ni300 AMed Steel in Extreme Loading and Temperature Conditions for Metal Cutting Applications

“…Rather than the typical high carbon content, the martensitic microstructure of AMed 18Ni300 maraging steel is achieved by nickel addition, which is the main element. The lack of carbon enhances weldability, which in turn makes such alloys a good choice for additive processing [24,25].…”