Effect of zirconia and aluminium titanate on the mechanical properties of transformation-induced plasticity-matrix composite materials

Abstract

Metal-matrix composite materials composed of an austenitic stainless steel with different ceramic particle reinforcements were investigated in this study. The test specimens were prepared via a powder metallurgical processing route with extrusion at room temperature. As reinforcement phase, either magnesia partially stabilized zirconia or aluminium titanate with a volume content of 5% or 10% was used. The mechanical properties were determined by quasi-static compressive and tensile loading tests at ambient temperature. The microstructure characteristics and failure mechanisms during deformation contributing to significant changes in strength and ductility were characterized by scanning electron microscopy including energy dispersive X-ray spectroscopy and electron back-scatter diffraction, and by X-ray diffraction. The composite materials showed higher stress over a wide range of strain. Essentially, the deformation-induced formation of α′-martensite in the steel matrices is responsible for the pronounced strain hardening. At higher degrees of deformation, the material behavior of the composites was controlled by arising damage evolution initiated by particle/matrix interface debonding and particle fracture. The particle reinforcement effects of zirconia and aluminium titanate were mainly controlled by their influences on martensitic phase transformations and the metal/ceramic interfacial reactions, respectively. Thereby, the intergranular bonding strength and the toughness of the steel/ceramic interfaces were apparently higher in composite variants with aluminium titanate than in composites with magnesia partially stabilized zirconia particles.

Metal‐Matrix Materials for High‐Temperature Applications with Liquid Aluminum

“…The high diffusivity and reactivity promote the formation of merging solid solutions with lenticular morphology in the system Ti–Mn–Al–O with minor fractions of Fe, Cr, and Si and of isolated rod‐like constituents based on the clearly different composition with weight fractions of 30% Al 2 O 3 , 10% MnO, and 60% TiO 2 . The microstructure of the composite materials with concurrent additions of TiO 2 and Al 2 O 3 largely complied with the observations of composite materials with additions of presynthesized aluminum titanate . Locations with higher concentrations of Si in the interstices between the coarser grained steel and the ceramic particles were assumed to origin from the polishing medium (SiO 2 ).…”

“…The rest was α'‐martensite and δ‐ferrite, which cannot be reliably distinguished due to their common bcc crystal structure. The phase composition of similar steel specimens usually alters during the thermal treatment of such powder metallurgically manufactured specimens as a result of the retransformation of martensite into austenite and/or intensive diffusional interactions between the metal and the ceramic component during sintering . The ferromagnetic fraction (martensite and ferrite) of the pure steel material was roughly 29% according to MSAT measurements.…”

“…The presence of carbides was not detected by the used methods throughout all the materials tested. The formation of nonmetallic particles and the intensive reactions between the metal and the ceramic components are characteristic of the conventional (pressureless) sintering of such materials, which implies a mutual influence on the chemical composition of both the matrix material and the ceramic particles . Alterations in the chemical composition, especially in the Cr and Mn content, promote an increase of the matrix's mean SFE in the composite variants as compared to the pure steel specimens.…”

Microstructure and Microhardness of ZrO2 Reinforced PM 316L Austenitic Stainless Steel Composites Sintered in Ambient and Argon Atmosphere

“…It has been reported that the water atomized steel powders have high oxygen content due to the thick oxide layer formed on the particle surface during production [16,17]. According to Y. Hedberg et al [18] the surface of water atomized steel particles are strongly enriched with oxidized Si (silicates).…”

Forming Complex Graded and Homogeneous Components by Joining Simple Presintered Parts of TRIP-Matrix Composite through Powder Forging

“…In particular, composites based on high-energy-absorbing transformation-induced plasticity (TRIP)/twinning-induced plasticity steels and transformable zirconia (ZrO 2 ) particles show great potential [20][21][22][23]. For instance, reinforcement with MgO-partially stabilized zirconia (Mg-PSZ) particles can increase the strength as well as the wear properties of these composites, owing to the ability of Mg-PSZ to undergo a stress-induced transformation from the tetragonal phase to the monoclinic phase [24][25][26]. Furthermore, the use of metastable austenitic steel as the matrix ensures a deformation-induced increase in both the strength and the ductility, owing to the TRIP effect [27,28].The aim of this study was to experimentally determine the forming conditions for the production of axially formed graded components from a particle-reinforced metal matrix composite using powder forging.…”