Effect Of Mo Content Research Articles

Effects of Mo content on the precipitation behavior and martensitic transformation in FeNiCoAlMo alloy

Effects of Mo content on the precipitation behavior and martensitic transformation in FeNiCoAlMo alloy

Effect of Mo Content on Microstructure and Fatigue Properties of Ni60 Coating Produced by Plasma Cladding

Effect of Mo Content on Microstructure and Fatigue Properties of Ni60 Coating Produced by Plasma Cladding

Effect of Mo content on the properties of graphite–MoC composites sintered by spark plasma sintering

Graphite–molybdenum–titanium powders prepared by colloidal processing technique were sintered by Spark Plasma Sintering (SPS). This material is proposed in this manuscript due to its potential interest as heat sink. The influence of the molybdenum content (2.5, 5.0 and 10.0vol.%) on the thermal, electrical, and mechanical properties of the composite are studied to define the composite with the best properties. Thermal, electrical, and mechanical properties of the composite graphite–10vol.% Mo–1vol.% Ti (that are composites of graphite with molybdenum and titanium carbides after sintering) are significantly better than those of the composites with lower molybdenum contents (2.5vol.% and 5vol.%). This way, flexural strength, electrical conductivity, and thermal conductivity are 1.5, 7.8 and 18 times greater, respectively, than in the composite graphite–2.5vol.% Mo–1vol.% Ti. In the case of comparing with the composite graphite–5vol.% Mo–1vol.% Ti, flexural strength, electrical conductivity, and thermal conductivity are 1.2, 5.1 and 3.2 greater in the composite graphite–10vol.% Mo–1vol.% Ti, respectively.

Development of high strength high plasticity refractory high entropy alloy based on Mo element optimization and advanced forming process

Refractory high entropy alloy is a potential substitute material for high temperature structures because of its excellent mechanical properties of high temperature resistance. In this paper, three kinds of refractory high-entropy alloys, M0, M10 and M20, were designed by adjusting the content of Mo element and formed by Laser powder bed melting(LPBF) technology. The solidification thermodynamics, microstructure and mechanical properties of the three kinds of alloys were analyzed. The effect of Mo content on the microstructure and mechanical properties of the three kinds of alloys was studied. With the increase of Mo element content, the grain size of the alloy becomes smaller and smaller, the yield strength increases greatly, and the plasticity of the alloy decreases continuously. The compressive yield strength of high strength M20 alloy is up to 1285 MPa, the ultimate strength is 2447 MPa, and the elongation is 27%. The high plasticity M0 alloy exhibits compressive superplasticity. The tensile yield strength and ultimate strength of M10 alloy are 1184 MPa and 1403 MPa, and the elongation is 5.1%. In this paper, the matching problem between plasticity and strength of refractory high-entropy alloys at room temperature is solved by combining alloy composition optimization and LPBF forming technology, which lays a foundation for the industrial application of refractory high-entropy alloys.

Effect of Mo Content on Microstructure and Mechanical Properties of Laser Melting Deposited Inconel 690 Alloy

Inconel 690 alloy is widely used in nuclear power, petrochemical, aerospace, and other fields due to its excellent high-temperature mechanical properties and corrosion resistance. The Inconel 690 alloy with different Mo content was fabricated by laser melting deposition (LMD). The effects of Mo content on the microstructure and mechanical properties were investigated. The microstructure of as-deposited Inconel 690 is composed of columnar dendrites grown epitaxially, and M23C6 carbides are precipitated in the grain boundaries. With the increase of Mo content, the amount of precipitated carbide increases gradually. At the same time, the grain boundary becomes convoluted. The tensile test at room temperature shows that the high Mo content in the as-deposited Inconel 690 increases the ultimate strength but decreases the ductility. Compared with low Mo content, the alloy with high Mo deposition has better mechanical properties. The present study provides a new method to achieve the preparation of Inconel 690 alloy with excellent integrated mechanical properties.

Effect of Mo in Ni-30Cr filler metal on the eutectic phases of weld metal

The effects of Mo content on the microstructure and solidification path of gas tungsten arc welding deposited Nb-bearing nickel-based alloy welding wire were studied. The Mo entered the matrix γ phase as a solid solution and was precipitated in the form of the eutectic phases including Laves, σ, and MC carbides. In Ni-30Cr weld metal, Mo plays a leading role in the eutectic σ formation, while a relatively minor role in the eutectic MC carbides and Laves formation compared with Nb. The addition of Mo could reduce the content of Nb in the dendrite arm, interdendritic region, and Laves phase. With the increasing Mo content, the Laves phase changed from a rod-like shape to a blocky shape. When the Mo content exceeded 4%, σ + Laves + γ eutectic structure was formed. When the Mo content was about 5.0%, there were microcracks in the σ and Laves phases, and at the σ/MC interface. To avoid the formation of the σ phase due to the segregation of Mo, the Mo content had to be controlled below 4%.

Microstructure and Properties of Ti-Zr-Mo Alloys Fabricated by Laser Directed Energy Deposition.

The binary Ti-Zr congruent alloys have been a potential candidate for laser-directed energy deposition owing to an excellent combination of high structural stability and good formability. To solve its insufficient strength, a new series of Ti-Zr-Mo alloys with different Mo contents were designed based on a cluster model and then made by laser-directed energy deposition on a high-purity titanium substrate. The effect of Mo content on the microstructure and properties of the L-DEDed alloys was investigated. The consequences exhibit that the microstructure of all designed alloys is featured with near-equiaxed β grains without obvious texture. However, increasing Mo content induces a gradual refinement of the grain and a steady decrease in the lattice constant, which effectively improves the hardness, strength, wear and corrosion resistance of the designed alloys, but slightly weakens ductility and formability. From the viewpoint of both properties and forming quality, the Ti60.94Zr36.72Mo2.34 (at.%) alloy owns a proper match in mechanical, tribological, chemical, and forming properties, which is widely used in aeroengine components.

Effect of Mo on the morphology, microstructure and mechanical properties of NbTa0.5TiMox refractory high entropy alloy fabricated by laser powder bed fusion using elemental mixed powders

The production of refractory metal pre-alloy powder is difficult and the related production cost is high. In this paper, NbTa0.5TiMox series refractory high entropy alloy was prepared by laser powder bed fusion (L-PBF) with elemental mixed powders. The effects of Mo content on the morphology, microstructure, hardness, density, and compression properties of the NbTa0.5TiMox alloy were studied. All NbTa0.5TiMox alloys fabricated by L-PBF present a single-phase BCC. Typical dendrites are formed within the grains and the elements are enriched in the dendrite trunk and inter-dendrite region from inside to outside depends on the melting point of the different materials. It was observed that the Mo content improves significantly the hardness and compressive strength of the alloy by solution strengthening. NbTa0.5TiMo1.0 alloy has the highest yield strength (1609 MPa), but with reduced ductility, while NbTa0.5TiMox (x ≤ 0.5) alloy has excellent ductility (e > 80%) at room temperature. The increase in Mo content leads to the increase of cracks, pores and non-penetration defects, resulting in the loss of sustained strength & ductility and decrease in density. The results provide a basis for the design and preparation of ductile refractory high entropy alloys by L-PBF of elemental mixed powders.

Effect of Mo content on impact toughness of CGHAZ in offshore engineering steels at different low temperatures

The effect of Mo content on impact toughness of the coarse-grained heat-affected zone (CGHAZ) in 420 MPa offshore engineering steels after 15 kJ/cm welding simulations is studied at low temperatures of −40, −60 and −80 °C. With increasing Mo content from 0.08 to 0.16 wt.%, the average size of the prior austenite grain in the CGHAZ is decreased from 150 to 70 µm, which mainly consists of lath bainite (LB). The fraction of high-angle grain boundaries (HAGBs) increases from 45.3% to 58.2%. The EBSD characterizations on the propagation and deflection of the main and secondary cracks in the CGHAZ indicate that the cleavage planes of the main crack mainly comprise of {100}, {110} and {112}. The way of fracture is changed from ductile fracture to quasi-cleavage fracture and cleavage fracture with decreasing the impact test temperature. As the Mo content is increased from 0.08 to 0.16 wt.%, the impact toughness values at −40, −60 and −80 °C are changed from 137, 101 and 40 J to 195, 117 and 88 J, respectively. With increasing the Mo content, the absorbed energies of the CGHAZ is improved because the sizes of PAG (Prior Austenite Grain) and LB are refined, and the fraction of HAGBs is increased to provide larger resistance for propagation of crack in CGHAZ.

Self-standing Mo-NiO/Ni electrocatalyst with nanoporous structure for hydrogen evolution reaction

Mo-Ni based materials are the favored catalysts for hydrogen evolution reaction (HER). In this work, we report the synthesis of nanoporous Mo-NiO/Ni electrocatalyst with self-standing structure through a simple dealloying method. The effect of Mo content on the morphology and electrochemical performance of the catalyst is investigated. The np-Mo6 sample delivers a low overpotential of 34 mV at 10 mA cm−2, a Tafel slope of 49 mV dec−1, and 100 h long-term stability of HER. The high specific surface area and suitable hydrogen adsorption/desorption energy contribute to the superior electrocatalytic activity and rapid kinetics. The self-standing structure prevents the loss of active components, which favors of the stability of the electrode.

Effects of Mo content on the microstructure and mechanical properties of TiNbZrMox high-entropy alloys

The single-phase TiNbZrMox (x = 0, 0.3, 0.5, 0.7, 1) high-entropy alloys (HEAs) were prepared by arc melting. The relation between molybdenum, microstructure, mechanical properties and wear resistance was investigated by X-ray diffractometer (XRD), scanning electron microscope (SEM), universal tensile tester, hardness tester, friction tester, and wear tester. The results showed that TiNbZrMox alloys were composed of a single BCC phase. With the increase of Mo elements, the crystallite size of the as-cast alloy decreased first and then increased, both the alloy strength and hardness were increased and compressive strain plasticity was decreased. TiNbZrMo0.5 has the best comprehensive performance with a yield strength of 1.0 GPa, compressive strength of 1.3 GPa, and hardness of 429 HV; compared with TiNbZrMo0, yield strength increased by 77.32%, compressive strength increased by 25.14%, and hardness increased by 70.24%; and its specific wear rate decreased by 50%, while it’s compressive plasticity only decreased by 5%.

Effects of Mo Content on the Microstructure and Performance of Tinbzrmox High-Entropy Alloys

Effects of Mo Content on the Microstructure and Performance of Tinbzrmox High-Entropy Alloys

Effects of Mo Content on the Precipitation Behavior and Martensitic Transformation in Fenicoalmo Alloy

Effects of Mo Content on the Precipitation Behavior and Martensitic Transformation in Fenicoalmo Alloy

Effects of Mo Content on the Microstructure and Mechanical Properties of Tinbzrmox High-Entropy Alloys

Effects of Mo Content on the Microstructure and Mechanical Properties of Tinbzrmox High-Entropy Alloys

Effect of Mo addition on residual stress and mechanical properties of SiC ceramic/Nb521 alloy joints brazed by using AgCuTi filler

Residual stress has great influence on the mechanical properties of ceramic/metal joints. In the study, SiC ceramic and Nb521 alloy were vacuum brazed by using AgCuTi filler, and Mo particles were added into the filler to reduce the residual stress of joint. The effects of Mo content on the microstructure and mechanical properties of the joints were systematically investigated. The addition of Mo effectively controlled the thickness of TiC + Ti5Si3 reaction layer nearby SiC ceramic. The suitable thickness of TiC + Ti5Si3 reaction layer could improve joint strength. The addition of Mo particles could also reduce the coefficient of thermal expansion (CTE) mismatch between base materials and filler. The shear strength reached 78.5 MPa with AgCuTi + 5 wt% Mo filler, which was 118% higher than the joint brazed with pure AgCuTi filler.

Effect of Mo content on Ti-Al-Mo ternary alloys for biomedical applications

The microstructure, microhardness, nano hardness, wear-resistance, and anti-wear properties of Ti6AlxMo ternary alloys (x = 3–15 wt%) have been studied for biomedical applications. The microstructural and phase analysis have demonstrated that there is an increase in the β phase with the increase in Mo wt%, while α and α2 phases decrease. Consequently, Ti6Al15Mo alloy has the lowest elastic modulus value. The highest micro and nano hardness values were exhibited by Ti6Al6Mo alloy owing to the presence of alpha and beta colonies with low interlayer distance in the microstructure. The hardness and wear resistance properties of Ti6Al15Mo alloys were comparatively higher than existing biomaterials like Ti6Al4V and CP Ti. The Ti6Al15Mo alloy can be considered as a promising new age biomaterial.

Effect of Mo content on nano-scaled particles, prior austenite grains and impact toughness of CGHAZ in offshore engineering steels

Effect of Mo content on nano-scaled particles, prior austenite grains and impact toughness of CGHAZ in offshore engineering steels

Effect of Mo Content on the Thermal Conductivity and Corrosion Resistance of Die Steel

Effect of Mo Content on the Thermal Conductivity and Corrosion Resistance of Die Steel

The effect of molybdenum content on the microstructural evolution and tensile properties of as-cast Ti-Mo alloys

The effect of Mo content on the microstructural evolution and the tensile properties of as-cast binary Ti-Mo alloys is designed by using the cluster-plus-glue atomic model and the β prediction method, such as the Moeq, e/a ratio and the d-electron, which were used to predict the stability of the β phase. The designed (Ti-10.02 wt % Mo, Ti-10.83 wt % Mo, Ti-12.89 wt % Mo and Ti-15.05 wt % Mo) alloys were fabricated by using the commercial arc re-melting furnace; and they were characterised for phase identification by using X-ray diffraction (XRD), the optical microscope (OM), the scanning electron microscope (SEM) and the electron backscatter diffraction (EBSD) techniques. The tensile properties of all the designed alloys were also analysed. The XRD spectra of all the designed alloys comprised the body-centred cubic (BCC) β phase and the orthorhombic martensitic (α″) phase. The orthorhombic martensitic peaks decreased with the increase in the Mo content. The Vickers microhardness (473.6, 440.6, 412.6 and 350.2 HV0.5) and the elastic modulus (112.99, 105.7, 104.47 and 70.48 GPa) decreased significantly with an increase in the Mo content, from 10.02 wt % Mo to 15.05 wt % Mo, respectively. The ultimate tensile strength (UTS) decreased significantly (885.45, 643.10 and 593.48 MPa) with an increase in the concentration of Mo from 10.83 wt % to 15.05 wt %. The fractured surfaces after the tensile test showed that the as-cast Mo content increased while the brittle fractures became the dominant fractures.

Effect of Mo Addition on the Mechanical and Wear Behavior of Plasma Rotating Electrode Process Atomized Ti6Al4V Alloy

In the current study, the effect of Mo content (1-10 wt.%) on the microstructure, hardness, bending and wear properties of Ti6Al4V-xMo alloys was investigated. The pre-alloyed and Plasma Rotating Electrode Process (PREP) atomized Ti6Al4V alloy powders and elemental Mo particles were mechanically mixed for 45 min in a zirconia jar. A uniaxial vacuum hot pressing was applied at 950°C for 30 min under 50 MPa pressure. The Ti6Al4V-xMo alloys were prepared metallographically and characterized by optical and scanning electron microscopy. The chemical composition of the different zones in the structure was determined using energy-dispersive x-ray (EDX) analysis. Mo appeared among the TiAl64V alloy particles and caused the formation of different diffusion zones. The formation of grain boundary α was effectively prevented, and instead, fine α’ and β zones were formed. Various phases formed along the particle boundaries of the Ti6Al4V alloy, and effective improvements in hardness, bending and wear resistance were obtained. However, the highest Mo content caused a decrease in mechanical properties. Ti6Al4V-5Mo alloy showed superior hardness and wear resistance.