scholarly journals Influencing the Mechanical Properties of Engine and Vehicle Constructions Alloy with Laser Surface Heating

2018 ◽  
Vol 47 (4) ◽  
pp. 295-301
Author(s):  
Lenka Kuchariková ◽  
Eva Tillová ◽  
Juraj Belan ◽  
Denisa Závodská
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloys ◽  
Energy Saving ◽  
Surface Hardening ◽  
Cast Alloy ◽  
Permanent Deformation ◽  
Laser Surface ◽  
Surface Heating ◽  
Great Opportunity ◽  
Hydraulic Unit

The self-hardening aluminum alloys are interesting for producers of casting, because these materials have the required properties without using heat treatment. This casts production result in the following advantages: energy saving, reduction of the costs, no permanent deformation, largest casting dimensions possible, and so on. Nevertheless, it is well known that improvement of mechanical properties and structure of aluminum alloys can often significantly increase the lifetime of casting and reduce costs for fuel and reduction of environmental loading. The basic and energy saving method for improvement of mechanical properties of self-hardened alloys is surface hardening. Surface hardening improves properties such as: corrosion resistance, wear resistance and hardness. In regards this facts great interest in reducing the cost of components makes a great opportunity for use laser surface processing. Therefore this article deals with using laser surface heating and evaluations its influence onto mechanical properties of self-hardening ENAC-71100, i.e. AlZn10Si8Mg cast alloy. This alloy is especially used for engine and vehicle constructions, hydraulic unit and mound so the surface properties are important for application in industries. The results show that laser surface heating have influence on properties, but well defined conditions of heating are very important.

Unconventional Metallographic Methods for the Structural Characterization of Laser Hardened Al-Zn-Si Cast Alloy

2014 ◽  
Vol 782 ◽  
pp. 369-372 ◽  
Author(s):  
Eva Tillová ◽  
Mária Chalupová
Keyword(s):  
Mechanical Properties ◽  
Laser Beam ◽  
Surface Hardening ◽  
Laser Power ◽  
Cast Alloy ◽  
Alpha Phase ◽  
Laser Surface ◽  
Hydraulic Unit ◽  
Laser Surface Hardening ◽  
Eutectic Si

The laser surface hardening is method which provides increased mechanical properties of secondary (recycled) Al-Si cast alloys for automotive industry. Improvement of mechanical properties and structure of secondary aluminium alloys can often significantly increase the lifetime of casting and reduce costs for fuel and reduction of environmental loading. For study was used a laser beam Nd: YAG lasers, BLS 720, on the test samples of secondary cast alloy AlZn10Si8Mg. AlZn10Si8Mg cast alloy are used for engine and vehicle constructions, hydraulic unit and mould making without the need of heat treatment because this alloy is self-hardened. The effect of laser beam was evaluated with the laser power 50 W and 80 W on the surface of samples. The final microstructure of Al-alloys depend on the laser process parameters. The changes of microstructure after laser surface hardening was observed by using classical techniques of etching (standard black-white contrast - etching by 0.5 % HF, 10 % H3PO4and colour contrast - etching by Weck-Al) and deep etching with HCl. Due to the action of laser beam on the surface of the secondary alloy AlZn10Si8Mg there have been changes in the microstructure of the material. Melting area is alpha-phase with much fine columnar dendrites morphology without the presence of Si-particles and intermetallic phases. In the transition area were observed grain refinement of eutectic Si (finer and rounder Si particles) as the modify action of the laser. By increasing the laser power the microhardness of surface layers decreases. In the surface layer (80 W) were observed cracks due to uneven heat transfer of the material.

Effect of the laser surface treatment on structure and mechanical properties of AlZn 10 Si 8 Mg cast alloy

2017 ◽  
Vol 4 (5) ◽  
pp. 5973-5978
Author(s):  
Eva Tillova ◽  
Maria Chalupova ◽  
Lenka Kucharikova ◽  
Denisa Zavodska ◽  
Juraj Belan
Keyword(s):  
Mechanical Properties ◽  
Surface Treatment ◽  
Cast Alloy ◽  
Laser Surface ◽  
Laser Surface Treatment

scholarly journals Hopeful high-strength casting alloys based on Al―Mg―Ge(Si) ternary systems

2020 ◽  
Vol 2020 (01) ◽  
pp. 55-66
Author(s):  
N. P. Korzhova ◽  
◽  
T. M. Legka ◽  
Y. V. Milman ◽  
K. E. Grinkevich ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloys ◽  
Cast Alloy ◽  
High Strength ◽  
Ternary Systems ◽  
Eutectic Type ◽  
Eutectic Alloys ◽  
Binary Eutectic ◽  
Casting Aluminum ◽  
Multicomponent Eutectic

The relative analysis of phase equilibria in the Al-corner of the ternary phase diagrams of Al―Mg―Ge(Si) systems is carried out. Both systems are characterized by the presence of a quasi-binary cross-section of the eutectic type, which is shifted towards Mg-enriched alloys, and sufficiently width range existence of the univariant eutectic transformation L-Al + Mg2Ge(Si). The melting point of quasi-binary eutectic (-Al + Mg2Ge) in the Al―Mg–Ge system and (-Al + Mg2Si) in the Al―Mg―Si is 629 °С and 597 °С, respectively, and the content of the strengthening phase ((Mg2Ge or Mg2Si) in eutectics is 7% (vol.) и 13% (vol.). The properties of non-alloyed alloys with different volume content of eutectic are investigated and the basic compositions of alloys with the optimal strength/ductility ratio for subsequent doping are selected as well. Taking into account the coordinates of the corresponding eutectic transformations, the doping system with the participation of Zn, Cu and other elements is determined. The heat treatment regimes for multicomponent eutectic alloys were selected, to ensure precipitation of Zn(Cu)-nanoparticles that strengthen matrix solid solution. It was shown that according to the level of mechanical properties, these alloys belong to high-strength alloys with property ranges: -Al + Mg2Ge) ― В = 470―590 МPа, 0,2 = 350―520 МPа, = 8,0―15,5%; -Al + Mg2Si) ― В = 400―560 МPа, 0,2 = = 430―520 МPа, = 2,3–-4,5%. Using a complex U-like Nechenji―Kuptsov test, casting properties were determined and it was shown that the fluidity of (-Al + Mg2Si) alloy was 1,3 times higher than that of the AK7ch cast alloy. In terms of the combination of mechanical and casting properties, the new multicomponent eutectic alloys based on the Al―Mg―Ge(Si) ternary systems are superior to the best modern industrial casting aluminum alloys. Keywords: casting aluminum alloys, ternary Al―Mg―Ge(Si) systems, eutectic alloys, alloying, microstructure, mechanical properties, fluidity.

Microstructures of Rapidly Solidified Aluminum Alloys

1983 ◽  
Vol 28 ◽  
Author(s):  
J.W. Zindel ◽  
J.T. Stanley ◽  
R.D. Field ◽  
H.L. Fraser
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Aluminum Alloys ◽  
Melt Spinning ◽  
Metastable Phase ◽  
Laser Surface ◽  
Metastable Phase Diagram ◽  
Transmission Electron ◽  
Ternary Additions ◽  
Rapidly Solidified

ABSTRACTAn investigation was performed to study the origin and stability of microstructures in rapidly solidified aluminum alloys. Al-Ni and Al-Fe base alloys were rapidly solidified by means of laser surface melting and melt spinning techniques. Microstructures were studied using optical and transmission electron microscopy. The effect of microstructure on mechanical properties was also studied using microhardness measurements. The origin of the observed microstructural constituents will be explained in terms of features of the metastable phase diagram. The effect of ternary additions on stability will also be considered.

Severe plastic deformation of Al-1%Cu Alloy processed by a Simple Cyclic Extrusion Compression technique

2018 ◽  
Vol 1 (1) ◽  
pp. 77-90
Author(s):  
Walaa Abdelaziem ◽  
Atef Hamada ◽  
Mohsen A. Hassan
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Deformation Behavior ◽  
Cast Alloy ◽  
Surface Hardness ◽  
Grain Structure ◽  
Compression Technique ◽  
Cu Alloy ◽  
Cyclic Extrusion Compression

Severe plastic deformation is an effective method for improving the mechanical properties of metallic alloys through promoting the grain structure. In the present work, simple cyclic extrusion compression technique (SCEC) has been developed for producing a fine structure of cast Al-1 wt. % Cu alloy and consequently enhancing the mechanical properties of the studied alloy. It was found that the grain structure was significantly reduced from 1500 µm to 100 µm after two passes of cyclic extrusion. The ultimate tensile strength and elongation to failure of the as-cast alloy were 110 MPa and 12 %, respectively. However, the corresponding mechanical properties of the two pass CEC deformed alloy are 275 MPa and 35%, respectively. These findings ensure that a significant improvement in the grain structure has been achieved. Also, cyclic extrusion deformation increased the surface hardness of the alloy by 49 % after two passes. FE-simulation model was adopted to simulate the deformation behavior of the material during the cyclic extrusion process using DEFORMTM-3D Ver11.0. The FE-results revealed that SCEC technique was able to impose severe plastic strains with the number of passes. The model was able to predict the damage, punch load, back pressure, and deformation behavior.

Research Advance in Harmful Effects and Removal of Impurity Fe from Al and Al Alloys

2011 ◽  
Vol 295-297 ◽  
pp. 751-759 ◽  
Author(s):  
Hua Shen ◽  
Wei Dong Yang ◽  
He Liang ◽  
Guang Chun Yao
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloys ◽  
Pure Aluminum ◽  
Al Alloys ◽  
Precipitation Method ◽  
Filtration Method ◽  
Purification Methods ◽  
Research Advance ◽  
Harmful Effects

The presence of Fe and harmful effects on mechanical properties of pure aluminum and aluminum alloys are introduced. Several purification methods are reviewed, but all of them are of definite limitations. It is effective that precipitation method, filtration method and centrifugal division method are integrated.

scholarly journals Influence of Gating System Parameters of Die-Cast Molds on Properties of Al-Si Castings

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3755
Author(s):  
Štefan Gašpár ◽  
Tomáš Coranič ◽  
Ján Majerník ◽  
Jozef Husár ◽  
Lucia Knapčíková ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Computer Modelling ◽  
Permanent Deformation ◽  
Surface Hardness ◽  
Technological Parameters ◽  
Inlet System ◽  
Die Cast ◽  
Key Factor ◽  
Fine Grained Structure ◽  
Design Solutions

The resulting quality of castings indicates the correlation of the design of the mold inlet system and the setting of technological parameters of casting. In this study, the influence of design solutions of the inlet system in a pressure mold on the properties of Al-Si castings was analyzed by computer modelling and subsequently verified experimentally. In the process of computer simulation, the design solutions of the inlet system, the mode of filling the mold depending on the formation of the casting and the homogeneity of the casting represented by the formation of shrinkages were assessed. In the experimental part, homogeneity was monitored by X-ray analysis by evaluating the integrity of the casting and the presence of pores. Mechanical properties such as permanent deformation and surface hardness of castings were determined experimentally, depending on the height of the inlet notch. The height of the inlet notch has been shown to be a key factor, significantly influencing the properties of the die-cast parts and influencing the speed and filling mode of the mold cavity. At the same time, a significant correlation between porosity and mechanical properties of castings is demonstrated. With the increasing share of porosity, the values of permanent deformation of castings increased. It is shown that the surface hardness of castings does not depend on the integrity of the castings but on the degree of subcooling of the melt in contact with the mold and the formation of a fine-grained structure in the peripheral zones of the casting.

The influence of gadolinium on Al–Ti–C master alloy and its refining effect on AZ31 magnesium alloy

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Wenxue Fan ◽  
Hai Hao
Keyword(s):  
Mechanical Properties ◽  
Magnesium Alloy ◽  
Grain Refinement ◽  
Magnesium Alloys ◽  
Master Alloy ◽  
Cast Alloy ◽  
Az31 Magnesium Alloy ◽  
Synthesis Mechanism ◽  
Refining Effect ◽  
Master Alloys

Abstract Grain refinement has a significant influence on the improvement of mechanical properties of magnesium alloys. In this study, a series of Al–Ti–C-xGd (x = 0, 1, 2, 3) master alloys as grain refiners were prepared by self-propagating high-temperature synthesis. The synthesis mechanism of the Al–Ti–C-xGd master alloy was analyzed. The effects of Al–Ti–C-xGd master alloys on the grain refinement and mechanical properties of AZ31 (Mg-3Al-1Zn-0.4Mn) magnesium alloys were investigated. The results show that the microstructure of the Al–Ti–C-xGd alloy contains α-Al, TiAl3, TiC and the core–shell structure TiAl3/Ti2Al20Gd. The refining effect of the prepared Al–Ti–C–Gd master alloy is obviously better than that of Al–Ti–C master alloy. The grain size of AZ31 magnesium alloy was reduced from 323 μm to 72 μm when adding 1 wt.% Al–Ti–C-2Gd master alloy. In the same condition, the ultimate tensile strength and elongation of as-cast alloy were increased from 130 MPa, 7.9% to 207 MPa, 16.6% respectively.

scholarly journals Experimental investigation on a novel approach for laser surface hardening modelling

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
L. Orazi ◽  
A. Rota ◽  
B. Reggiani
Keyword(s):  
Surface Hardening ◽  
Carbon Diffusion ◽  
Industrial Applications ◽  
Laser Surface ◽  
Simplified Approach ◽  
Laser Surface Hardening ◽  
Novel Approach ◽  
Laser Treatments ◽  
High Flexibility ◽  
Short Time

AbstractLaser surface hardening is rapidly growing in industrial applications due to its high flexibility, accuracy, cleanness and energy efficiency. However, the experimental process optimization can be a tricky task due to the number of involved parameters, thus suggesting for alternative approaches such as reliable numerical simulations. Conventional laser hardening models compute the achieved hardness on the basis of microstructure predictions due to carbon diffusion during the process heat thermal cycle. Nevertheless, this approach is very time consuming and not allows to simulate real complex products during laser treatments. To overcome this limitation, a novel simplified approach for laser surface hardening modelling is presented and discussed. The basic assumption consists in neglecting the austenite homogenization due to the short time and the insufficient carbon diffusion during the heating phase of the process. In the present work, this assumption is experimentally verified through nano-hardness measurements on C45 carbon steel samples both laser and oven treated by means of atomic force microscopy (AFM) technique.

Sign in / Sign up

Export Citation Format

Share Document