scholarly journals Studies on the influence of Alti5b1 modifier on the structure and properties of alcumg ALLOYS

2021 ◽  
pp. 37-48
Author(s):  
Wojciech Ściężor ◽  
Radosław Kowal ◽  
Krystian Franczak ◽  
Justyna Grzebinoga ◽  
Paweł Kwaśniewski ◽  
...  

New materials used in various industries require sufficiently high mechanical properties, fine-grained structure and ease of metal forming while minimizing production costs. For this reason, work is being carried out to develop new groups of alloys that make it possible to increase the strength of the obtained components while reducing their weight, and thus reducing production costs. This article focuses on two aluminium-based alloys with different content of alloying additives: copper and magnesium i.e., AlCu3Mg3 and AlCu4.5Mg6, which were produced by metallurgical synthesis. The as-cast alloys were characterized for their basic physical, mechanical and electrical properties and were subjected to structural analysis. In the next stage, the alloys were modified with 100, 500, 1000 and 2000 ppm of titanium and then their hardness, electrical conductivity and density were tested. Samples were also subjected to microstructural analysis. The obtained results allowed to examine the evolution of the AlCuMg alloy properties depending on the content of alloy additives and the amount of used modifier.

2011 ◽  
Vol 291-294 ◽  
pp. 137-140
Author(s):  
Yao Min Zhu ◽  
Qiu Ran Gao ◽  
Feng Zhang Ren ◽  
Shi Jie Fang

The effects of the hot-rolling process on microstructures and strength were investigated for two kinds of magnesium alloy Mg-Zn-Y and Mg-Zn-Y-Nd. In comparison with the as-cast alloys, the tensile strength of Mg-Zn-Y and Mg-Zn-Y-Nd both increases 45%, whereas their elongation decreases 73%, 60% via hot-rolling process, respectively. The results show that the dynamic recrystallization process and the pining effect of I-phase during hot rolling contribute to the fine-grained structure formation. The hot-rolling process has refined the grain size greatly.


2021 ◽  
Vol 316 ◽  
pp. 426-432
Author(s):  
Raisa K. Mysik ◽  
Andrey V. Sulitsin ◽  
Vadim V. Morgunov

The article presents the results of pilot-industrial experiments in the field of manufacturing technology of contact wire made of Cu-Sn alloys. Cast rods with a diameter of 20 mm, made of CuSn0.04, CuSn0.1, CuSn0.2, CuSn0.3, CuSn0.4 alloys, were obtained in a continuous casting plant on an Upcast system. Cast rods were deformed using a Conform technology, and extruded billets with a diameter of 18 and 20 mm were produced, which were subsequently drawn on a shaped contact wire with a cross section of 100 mm2. Cast rods macrostructure and microstructure were studied. The macrostructure quantitative assessment of samples was studied in a cross and longitudinal section. A plot of the effect of the tin content in the alloy on the average grain area in cross section is obtained. An increase in the tin content in the alloy leads to a decrease in the average grain area. An analysis of the rod microstructure in a cross section showed that the structure is a grain of an α-solid solution of tin in copper, and the grain boundaries are thin and clean. After deformation by Conform technology a uniform fine-grained structure is ensured. The effect of the tin content in the alloy on the Brinell hardness of cast billets, made by Conform technology, is determined. An increase in the tin content in the alloy leads to an increase in the hardness of both cast and deformed billets. The microstructure analysis of the contact wire in the cross section is carried out. The mechanical and electrical properties of the contact wire with a cross section of 100 mm2 are determined. An analysis of the results showed when the tin content in the alloy is up to 0.4 wt. %, the required level of mechanical and electrical properties of the contact wire is not provided. It may be necessary to change the size of the initial billet before drawing or to increase the tin content in the alloy more than 0.4 wt. %.


2019 ◽  
Vol 85 (6) ◽  
pp. 30-36
Author(s):  
N. V. Lebedeva ◽  
Yu. M. Markova ◽  
A. I. Ziza ◽  
D. M. Anisimov

We present the results obtained using the equipment available at the Center for collective use “Composition, structure, properties of structural and functional alloys” NRC “Kurchatov Institute” — CRISM “Prometey”: DIL 805A/D (TA Instruments) and DIL 402C (Netzsch) dilatometers. Dilatometric analysis which provides determination of the temperature coefficient of linear expansion and the temperature of phase transitions, as well as evaluation of the transformation kinetics, can also allow simulation of heat treatment modes to identify the size of the former austenitic grain using vacuum etching and conduct the research aimed at improving the technology of thermal and thermomechanical processing (TMO) of steels and alloys. The experiments were carried out both in vacuum and in dynamic helium atmosphere. The main methodological difficulties that we have faced with are described. For steels of martensite and martensite-bainite class (38KhMA, 38KhN3MFA, 20Kh3NMFA) conditions of vacuum etching in the chamber of the dilatometer are specified. The efficiency of the method for martensite-bainite steels in determination of the grain size compared to traditional methods of etching is deminstrated. The effect of thermodeformation parameters on the size of austenitic grain is estimated. When modeling the heat treatment modes by the dilatometric method, the microstructure of KhN55MVTs nickel alloy was also analyzed. Changes in the size and morphology of the grain structure at different stages of heat treatment are revealed. The obtained results were used to adjust the current modes of heat treatment and obtain a uniform fine-grained structure. The combined application of dilatometric and metallographic analyzes after vacuum etching of the material decreases the production costs attributed to obtaining the desired microstructure upon thermal and thermomechanical processing of the products and blanks.


Author(s):  
Ivan Kovalenko

In the development of modern shipbuilding conditions and the repair of ship units, a special role is given to the use of basic structural elements consisting of technological parts. When performing these steps, it is important to analyze the properties of the materials from which the technological components of ship equipment are made. Testing should be close to the operating conditions of ship axles and shafts, namely cyclic loading, aggressive and adhesive environment. Therefore, a special factor is the technological control over the sequence of manufacture, selection of materials, surfacing technology. All these requirements can be analyzed and predicted using computer modulation. Investigations of the properties of the transition layers of the weld and the base metal and their effect on the number of load cycles in the tests are also key. All conditions will be met with the optimal selection of the chemical component Ni - Cr, which provide the required level of doping. The hardness of the materials is ensured by the presence of Mg in the metal. Also important are the heat treatment modes that provide the desired final structure of the material for machining and surfacing. For this part and its elements, the best properties in terms of operation in fine austenitic and pearlitic structures. During the operation of ship shafts and axles, the propagation of puncture loads is performed due to the occurrence of final stresses at low-cycle and multi-cycle loads and subsequent fatigue of the structural lattice. When considering the range of materials used in combined structures is very large and includes most welded steels. According to the combination of materials in one unit, it is advisable to distinguish two main groups of structures: with welded joints of steels of the same structural class, but different alloying, and with welded joints of steels of different structural classes. In this regard, the decision to obtain a balanced bandage connection lies in obtaining a fine-grained structure of the weld metal and the seam area.


2019 ◽  
Vol 70 (11) ◽  
pp. 3835-3842
Author(s):  
Mihai Dumitru Tudor ◽  
Mircea Hritac ◽  
Nicolae Constantin ◽  
Mihai Butu ◽  
Valeriu Rucai ◽  
...  

Direct use of iron ores in blast furnaces, without prior sintering leads to a reduction in production costs and energy consumption [1,2]. Fine-grained iron ores and iron oxides from ferrous wastes can be used together with coal dust and limestone in mixed injection technology through the furnace tuyeres. In this paper are presented the results of experimental laboratory investigations for establishing the physic-chemical characteristics of fine materials (iron ore, limestone, pulverized coal) susceptible to be used for mixed injection in blast furnace. [1,4]. The results of the experimental research have shown that all the raw materials analyzed can be used for mixt injection in blast furnace.


Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 41
Author(s):  
Tim Jurisch ◽  
Stefan Cantré ◽  
Fokke Saathoff

A variety of studies recently proved the applicability of different dried, fine-grained dredged materials as replacement material for erosion-resistant sea dike covers. In Rostock, Germany, a large-scale field experiment was conducted, in which different dredged materials were tested with regard to installation technology, stability, turf development, infiltration, and erosion resistance. The infiltration experiments to study the development of a seepage line in the dike body showed unexpected measurement results. Due to the high complexity of the problem, standard geo-hydraulic models proved to be unable to analyze these results. Therefore, different methods of inverse infiltration modeling were applied, such as the parameter estimation tool (PEST) and the AMALGAM algorithm. In the paper, the two approaches are compared and discussed. A sensitivity analysis proved the presumption of a non-linear model behavior for the infiltration problem and the Eigenvalue ratio indicates that the dike infiltration is an ill-posed problem. Although this complicates the inverse modeling (e.g., termination in local minima), parameter sets close to an optimum were found with both the PEST and the AMALGAM algorithms. Together with the field measurement data, this information supports the rating of the effective material properties of the applied dredged materials used as dike cover material.


1970 ◽  
Vol 3 (1) ◽  
pp. 15-22 ◽  
Author(s):  
SK Nath ◽  
Uttam Kr Das

Fracture toughness (K1C) of medium carbon steel (0.5% C) has been determined by round notched tensile specimen. Two notch diameters (5.6mm and 4.2mm) and three notch angles (α) namely 45°, 60° and 75° have been used to observe the effect of notch diameters and notch angle on fracture toughness of the steel. By heat treatment the microstructure of the steel is also varied and its effect on the fracture toughness is also observed. It has been found that fine grained structure improves fracture toughness. Lower notch diameter and higher notch angle show higher value of K1C. Keywords: Fracture toughness, microstructure, notch, heat treatmentDOI: 10.3329/jname.v3i1.925 Journal of Naval Architecture and Marine Engineering 3(2006) 15-22


2010 ◽  
Vol 37-38 ◽  
pp. 64-67
Author(s):  
Jin Song Chen ◽  
Yin Hui Huang ◽  
Bin Qiao ◽  
Jian Ming Yang ◽  
Yi Qiang He

The principles of jet electrodeposition orientated by rapid prototyping were introduced. The nanocrystalline nickel parts with simple shape were fabricated using jet electrodeposition. The microstructure and phase transformation of nanocrystalline nickel were observed under the scanning microscope and X-ray diffraction instrument. The results show that the jet electrodeposition can greatly enhance the limited current density, fine crystalline particles and improve deposition quality. The nickel parts prepared by jet electrodeposition own a fine-grained structure (average grain size 25.6nm) with a smooth surface and high dimensional accuracy under the optimum processing parameters.


2012 ◽  
Vol 201-202 ◽  
pp. 1102-1105
Author(s):  
Jin Song Chen ◽  
Jian Ming Yang

The principles of jet electrodeposition orientated by rapid prototyping were introduced , The nanocrystalline nickel parts with simple shape were fabricated using jet electrodeposition oriented by rapid prototyping. The microstructure and phase transformation of nanocrystalline nickel were observed under the scanning microscope and X-ray diffraction instrument . The results show that the successful fabrication of metallic parts demonstrates the potential of the jet electrodeposition process for prototyping technology . The jet electrodeposition can greatly enhance the limited current density, fine crystalline particles and improve deposition quality. The nickel parts prepared by jet electrodeposition own a fine-grained structure( average grain size 25.6nm) with a smooth surface and high dimensional accuracy under the optimum processing parameters..The dimensional accuracy as well as the surface quality of metallic parts and tools manufactured using jet electrodeposition techniques still lag far behind those of conventionally machined parts.


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