Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Powiadomienia systemowe

Sesja wygasła!

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: stop magnezu WE54

Sortuj według:

Ogranicz wyniki do:

Effect of Deep Cryogenic Treatment Time on Micromechanical and Tribological Properties of Magnesium Alloys WE43 and WE54

Barylski Adrian, Aniołek Krzysztof

Tribologia

2022

nr 4

7--16

The paper presents the effect of deep cryogenic treatment time on micromechanical and tribological properties of magnesium alloys, WE43 and WE54. The alloys were subjected to deep cryogenic treatment at a liquid nitrogen temperature (-196°C) for 2 to 48h. Tribological tests were performed in a rotational and a reciprocating linear motion, and wear trace studies were performed by profilometric and microscopic measurements. The tests indicate that deep cryogenic treatment has a favourable effect on the micromechanical, mechanical and tribological parameters of the two investigated alloys. It has also been shown that sub-zero treatment time significantly impacts the cryogenic treatment result. Among other things, there was a nearly 10% increase in hardness, Young's modulus, and a 35% reduction in tribological volumetric wear resulting from the improvement in mechanical properties, as well as a 2-fold reduction in linear wear with an increase in sub-zero treatment time relative to the material in its as-delivered state. Deep cryogenic treatment with appropriately selected sub-zero treatment time allows for improving the service life of magnesium alloys with rare earth metals.

W artykule przedstawiono wpływ czasu głębokiej obróbki kriogenicznej na właściwości mikromechaniczne oraz tribologiczne stopów magnezu WE43 i WE54. Stopy poddano głębokiej obróbce kriogenicznej w temperaturze ciekłego azotu (-196°C) w czasie od 2 do 48 h. Testy tribologiczne wykonano w ruchu obrotowym oraz w ruchu posuwisto-zwrotnym liniowym. Badania śladów zużycia wykonano za pomocą pomiarów profilografometrycznych oraz mikroskopowych. Przeprowadzone testy wskazują, że głęboka obróbka kriogeniczna wpływa korzystnie na parametry mikromechaniczne, mechaniczne i tribologiczne obu badanych stopów. Wykazano również, że istotne znaczenie na efekt obróbki kriogenicznej ma czas wymrażania. Stwierdzono między innymi blisko 10% wzrost twardości modułu Younga oraz wynikające z poprawy właściwości mechanicznych – 35% ograniczenie zużycia tribologicznego objętościowego i 2-krotne obniżenie zużycia liniowego wraz ze wzrostem czasu wymrażania w stosunku do materiału w stanie dostawy. Głęboka obróbka kriogeniczna o odpowiednio dobranym czasie wymrażania pozwala na poprawę trwałości eksploatacyjnej stopów magnezu z metalami ziem rzadkich.

The influence of ageing on structure and mechanical properties of WE54 alloy

Kiełbus A.

Journal of Achievements in Materials and Manufacturing Engineering

2007

Vol. 23, nr 2

27-30

Purpose: WE54 magnesium alloy offers attractive properties for aerospace and automotive industries. It reaches high specific strength, creep resistance and corrosion resistance up to a temperature of 250 degrees centigrade. The alloy contains 5%wt.Y, 1.7%wt.Nd and 0.55%wt.Zr. The strength of this alloy is achieved essentially via precipitation strengthening. Depending on the ageing temperature and time, the precipitation sequence in WE alloys has been reported to involve formation of phases designated beta", beta' and beta. The aim of the research was to determine the effect of ageing parameters on the microstructure and mechanical properties of WE54 magnesium alloy. Design/methodology/approach: Solution treatment was performed at 525 degrees centigrade/8h with water cooling. Ageing treatments were performed at 250 degrees centigrade/4-96h in air. The microstructure was characterized using Transmission Electron Microscope (TEM). The examination of the mechanical properties was conducted on an MTS-810 machine at two temperatures: ambient and 200 degrees centigrade. Hardness measurements by Vickers method were performed on a ZHV50 hardness tester. Findings: The microstructure of the WE54 alloy in as-cast condition consists of alpha-Mg phase matrix with some fine-dispersion precipitates of Mg2Y and Mg24Y5 intermetallic phases inside and on grain boundaries. After solution treatment followed by water-cooling, the intermetallic phases dissolve in the matrix. The ageing treatment caused precipitation of beta", beta' and beta 1 intermetallic phases. The best mechanical properties (Rm=333MPa, R0,2=257MPa, A5=6,3%) has a alloy with beta' intermetallic phase after ageing at 250 degrees centigrade/16h. Research limitations/implications: The future research will contain corrosion and creep tests of WE5 magnesium alloy. Practical implications: The established heat treatment parameters can be useful for preparing heat treatment technology of WE54 casts. Originality/value: The relationship between the ageing parameters, microstructure and mechanical properties in WE54 magnesium alloy was specified.