Wyniki wyszukiwania - BazTech

1

Review of Magnesium Alloys Used in the Manufacture of Wheels for Light Vehicles

Siemionek Ewa, Majerski Krzysztof, Surdacki Piotr, Novakova-Marcincinova Ema

Advances in Science and Technology. Research Journal

|

2023

|

Vol. 17, no 6

245--253

EN

This article provides an overview of the materials used to manufacture magnesium wheels for light vehicles. The analysis was conducted with the aim of developing a new, efficient technology for molding magnesium alloy wheels for light vehicles from preforms cast into metal molds. The knowledge accumulated so far on materials and their properties for the production of magnesium wheels will allow the design of a new technology for molding rims from materials of superior quality and durability. Currently, magnesium wheels are mainly produced from cast magnesium alloys and magnesium alloys for forming. Cast magnesium alloys used for magnesium wheels include AZ91, AM50, AM60, AE44, ZK61, ZE41, EZ33, EQ21, WE43 and the newly developed Mg-2.96Nd-0.21Zn-0.39Zr alloy. Magnesium metal-forming alloys used for magnesium wheels include AZ31, AZ61, AZ80 and ZK30, ZK60. The study includes an analysis of their properties and application examples.

2

Mechanical Property Comparison of Al11Si Wheels Grain Refined by Ti, Nb and MTS

Aydogan F., Dizdar Kerem Can, Sahin Hayati, Mentese E., Dispinar Derya

Archives of Foundry Engineering

|

2022

|

Vol. 22, iss. 4

14--18

EN

In this work, 25 wheels were cast with three different grain refiners: Al5Ti1B, Al3Nb1B and MTS 1582. Samples were machined from the wheels to check the mechanical properties. It was found that Nb grain refinement had the lowest grain size (260 mm) and highest tensile properties (yield strength of 119-124 MPa and ultimate tensile strength of 190-209 MPa). Al5Ti1B and MTS 1582 revealed quite similar results (110 MPa yield and 198 MPa ultimate tensile strength). The fading of the grain refining effect of Al5TiB1 master alloy was observed in both Nb and Ti added castings whereas during the investigated time interval, the fading was not observed when MTS 1582 was used.

3

Aluminum Alloy Development for Wheel Production by Low Pressure Die Casting with New Generation Computational Materials Engineering Approaches

Yağcı T., Cöcen Ü., Çulha O.

Archives of Foundry Engineering

|

2021

|

Vol. 21, iss. 4

35--46

EN

Computational Materials Engineering (CME) is a high technological approach used to design and develop new materials including the physical, thermal and mechanical properties by combining materials models at multiple techniques. With the recent advances in technology, the importance of microstructural design in CME environments and the contribution that such an approach can make in the estimation of material properties in simulations are frequently discussed in scientific, academic, and industrial platforms. Determination of the raw material characteristics that can be modeled in a virtual environment at an atomic scale by means of simulation programs plays a big role in combining experimental and virtual worlds and creating digital twins of the production chain and the products. In this study, a new generation, alternative and effective approach that could be used to the development of Al-Si based wheel casting alloys is proposed. This approach is based on the procedure of optimizing the physical and thermodynamic alloy properties developed in a computer environment with the CME technique before the casting phase. This article demonstrates the applicability of this approach in alloy development studies to produce Al-Si alloy wheels using the low pressure die casting (LPDC) method. With this study, an alternative and economical way is presented to the alloy development studies by trial and error in the aluminum casting industry. In other respects, since the study is directly related to the automotive industry, the reduction in fuel consumption in vehicles is an expected effect, as the new alloy aims to reduce the weight of the wheels. In addition to conserving energy, reducing carbon emissions also highlights the environmental aspects of this study.

4

The effect of filter type on filling during Low Pressure Die Casting: a numerical study

Yavuz H., Kara A., Çubuklusu H. E., Çe Ö. B., Aybarç U.

Journal of Achievements in Materials and Manufacturing Engineering

|

2016

|

Vol. 75, nr 2

71--77

EN

Purpose: Effect of filter types on filling during low pressure die casting researched to find optimal filtration design for wheel casting process. Design/methodology/approach: Three types of filters, which are commonly used during low pressure die casting for light alloy aluminium wheel production, investigated with numerical simulation. In addition, numerical simulation for without filter is made for control variable. According to numerical simulation results, filling time, molten metal velocity results are used to define suitability of the molten metal for wheel casting. Thirteen Control points and two filtration areas generated to calculate the molten metal velocities before and after the filtration areas. Findings: Three different filtration designs for aluminium wheel casting compared according to molten aluminium velocity results of numerical simulation in terms of flow of melt. Filtration design with flat filter is the optimal filtration design for aluminium wheels casting, according to numerical simulations. In addition, combination of other filters with flat filter is suggested to find optimal filtration design according to performance of filters during low pressure die casting. Research limitations/implications: 0.5 m/s velocity for molten metal is accepted as a critical maximum limit for reliable casting according to literature search on aluminium casting. No field test was done in this study. Originality/value: Effect of flow properties on casting quality is promising research field and the effect of filters is part of this research field.

5

Wpływ zużycia łożysk kół jezdnych pojazdu na zmiany sygnału ciśnienia akustycznego

Wojnar G., Stanik Z.

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2010

|

z. 66

117-122

PL

W artykule przedstawiono wpływ zużycia łożysk kół jezdnych samochodu na zmiany ciśnienia akustycznego, występującego we wnętrzu kabiny. Sygnały akustyczne zarejestrowano w warunkach drogowych przy zmiennej w czasie prędkości jazdy. Na podstawie przeprowadzonych analiz określono zakres prędkości pojazdu, w którym zmiany ciśnienia akustycznego, powodowane zużyciem łożysk kół, są najbardziej znaczące.

EN

The following study presents the influence of the wear of the wheels' bearings on the acoustic pressure occurring in the cabin of car. The acoustic signals were registered in the road conditions with the variable during the travelling speed. On the basis of the results, the range of vehicle's travelling speed was determined. The changes of the acoustic pressure in the vehicle caused by the wear of the wheel's bearings proved to be important.

6

Diagnostyka kół pojazdów szynowych

Kosmol J.

Prace Naukowe Katedry Budowy Maszyn / Politechnika Śląska

|

2009

|

nr 1

17-28

PL

W artykule przedstawiono pewną metodę wyznaczania średnicy koła pojazdu szynowego, znajdującego się w ruchu. Metoda ta bazuje na oryginalnej koncepcji układu pomiarowego kąta obrotu dźwigni obrotowej, której jeden koniec styka się z bieżnią koła mierzonego. Przedstawiono analityczne zależności, na podstawie których wyznacza się chwilową wartość promienia koła, dysponując z pomiarów, czasowym przebiegiem kąta obrotu dźwigni. Na podstawie badań symulacyjnych wykazano, że bazując na dostępnych rynkowo czujnikach kąta obrotu typu przetworniki obrotowo-impulsowe możliwe jest zidentyfikowanie różnicy dwóch kół mniejszej niż 1 mm, co spełnia wymogi wynikające z norm odnośnie konieczności regeneracji kół. Przedstawiono także strategię wyznaczania średnicy koła, bazując na pomiarach kąta obrotu dźwigni.

EN

In the article a method of identification the diameter of wheel of a rail vehicle being in movement was introduced. The method based on original conception of arrangement of measuring angle turn rotary lever which one end puts together from track of the measured wheel. Analytic dependences were introduced, on basis which the temporary value of radial of wheel was identified, having from measurements, the temporary course of angle of turn lever. Based on simulating investigations it was shown, that having accessible sensors of angle of turn type like encoders - possible identifying the difference two wheels is smaller than 1 mm. This fulfils the resulting with norms requirements regarding the necessity of regeneration of wheels. The strategy of identification the diameter of wheel was introduced, based on measurements of angle of turn lever, as well.

7

The influence of dry, rolling-sliding friction conditions on the wear of a rail steel mated with hardened tyre steel

Witaszek M., Bąkowski H.

Tribologia

|

2007

|

nr 3-4

389-400

EN

Polish State Railways introduced recently hardening of some part of profile of wheel tyres, for some types of locomotives. The aim of it was to improve their wear resistance. But hardened wheels can influence the wear behaviour of rails. In this work the wear rate and mechanisms of rails mated with hardened wheels has been studied wit the aid of laboratory wear tests. The wear tests have been performed on an Amsler, twin disc testing machine. Their results enabled assessment of creep, pressure and rotating speed effect on the wear behaviour of rail steel grade 900A. The influence of creep in the tested range was the most significant. Its increase up to a critical value, which ranged from 3% to 4% (according to the applied pressure and speed), increased the wear rate over an order of magnitude. That growth was caused by a wear mechanism transition from contact fatigue to adhesion and cracking of highly deformed material beneath the contact surface. If slippage overstepped the critical value, wear rate dropped off because of oxidation of wearing surfaces. The influence of pressure and rotating speed on the studied wear rate was in tested span less significant than the one of creep. Heightening of a pressure increased the wear rate, since an intensification of the plastic deformation of material beneath the wearing surface and thus its cracking and wear debris formation. Rotating speed growth lowered wear rate since it intensified a frictional heating and rubbing surface oxidation.

PL

Wprowadzenie w ostatnim czasie, przez Polskie Koleje Państwowe, hartowania obręczy kół wybranych serii lokomotyw spowodowało podjęcie w niniejszej pracy badań zużywania szyn współpracujących z kołami o wysokiej twardości. Badania te przeprowadzono na stanowisku Amslera, w układzie rolka - rolka. Ich wyniki pozwoliły na ocenę wpływu poślizgu, nacisku i prędkości obrotowej na intensywność i wiodące mechanizmy zużywania próbek wykonanych ze stali szynowej gatunku 900A. Stwierdzono, że w badanym zakresie, wpływ poślizgu na tę intensywność jest najistotniejszy. Wzrost poślizgu od 0,3% do wartości krytycznej (3-4%) wywołuje jej zwiększenie się wskutek zmiany wiodącego mechanizmu zużywania ze zmęczenia stykowego na adhezję i doraźne pękanie silnie odkształconego materiału warstwy wierzchniej. Dalszy wzrost poślizgu, do 5%, wywołuje zmniejszenie się intensywności zużywania wskutek obecności tlenków na zużytej powierzchni. Zbadany wpływ nacisku i prędkości obrotowej próbek na intensywność zużywania próbek ze stali szynowej jest mniejszy niż poślizgu. Zwiększenie nacisku podwyższa intensywność zużywania, dzięki wzrostowi odkształcenia plastycznego materiału warstwy wierzchniej, sprzyjającemu jego dekohezji. Wpływ prędkości obrotowej jest przeciwny, z powodu intensyfikacji utleniania powierzchni roboczej, przeciwdziałającego adhezji.