scholarly journals Mechanisms of structural-phase transformations during crystallization of solder melt under conditions of magnetic-dynamic influences for carbide tools

Author(s):  
Anatoliy Kuzey ◽  
Vladimir Lebedev ◽  
Pavel Tsykunov ◽  
Andrey Slipchuk

The processes of melt formation were studied by methods of optical and electron scanning microscopy. These processes occur during induction brazing of a hard alloy to a steel holder and contact interaction of low-melting (copper-zinc system alloy) and refractory (iron-nickel) components of the solders. It is shown that the effect of a thermal and magnetic-dynamic high-frequency electromagnetic field on the components of the composite solder is how a high-strength solder joint is formed. The structure is forming by disperse hardening mechanism. The research of the contact interaction process for low-melting and high-melting components of solders during the soldering process of the tool showed that the formation of solder in brazed seams occurs through a number of stages and this does not lead to the formation of microstructures that are characteristic of alloys based on copper-iron-phosphorus, copper-zinc-nickel and copper-zinc-iron. Thus, the use of composite solders can reduce the soldering temperature by 40-50 K and increase the concentration of alloying species in the solder and change its structure. These advantages of composite solders reduce the thermal impact on contact materials, increase the strength of the weld and allow you to control the thickness of the brazed weld, and this is important when soldering hard alloys of WC-TiC (TaC) systems. High initial dissolution rates of nickel particles in the copper-zinc melt and the solubility of copper, zinc in nickel lead to the formation in the melt of quasi-liquid particles of the nickel alloy. When the melt is cooled, particles other than the surrounding alloy composition are formed. They are morphologically related to the grain structure of the solder. The formed alloy (solder) has the structure of a composite material in which the metal particles are enriched in nickel, and have the role of a reinforcing element.

Author(s):  
Anatoliy Kuzey ◽  
◽  
Vladimir Lebedev ◽  
Andrii Slipchuk ◽  
Pavel Tsykunov ◽  
...  

Problem statement. An important requirement is quality assurance of joining materials with minimal overheating of materials, lowering the soldering temperature and suppressing the interaction of the solder with the materials to be soldered. The heating of the solder and the holder should be as uniform as possible and with a minimum temperature difference along the depth. One solution may be to develop more efficient solders and fluxes, adapted to the high heating rates that are typical when using high frequency currents Purpose. Thus, the problems of uniform heating of parts during brazing are relevant. This is necessary for optimal distribution of the electromagnetic field in the contact area Methodology. The effect of the heating rate was investigated. The composition of the flux and solders on the microstructure of the solders and the brazed seam was performed on the joints of HV510 (DIN), HS345 (DIN), HG30 (DIN) hardmetal plates with steel holders made of 5135 (USA) steel with a section of 25×20. Results. The research of the processes showed that during the contact interaction of low-melting and refractory components of the solders, when the tool was soldered, the solder is formed in the seam and proceeds through several stages. Practical value. Contact interaction of copper-zinc melts with iron particles does not lead to complete dissolution of iron particles. This is explained to the low values of the solubility of iron in copper-zinc melts despite the fact that resistive heat release occurs in the particles. Such iron particles (iron-based alloy) act as a dispersed phase in the structure of the composite material.


Alloy Digest ◽  
1954 ◽  
Vol 3 (12) ◽  

Abstract NAVAL BRASS is a copper-zinc alloy, containing 3/4% of tin, having high strength, toughness and resistance to corrosion. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-21. Producer or source: Brass mills.


Alloy Digest ◽  
1971 ◽  
Vol 20 (1) ◽  

Abstract BRIMCOLLOY is a copper-zinc tin alloy having high strength, spring temper, superior conductivity and high corrosion resistance. It is produced in three grades: BRIMCOLLOY 100, BRIMCOLLOY 200, and BRIMCOLLOY 300. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Cu-225. Producer or source: Bridgeport Rolling Mills Company.


Alloy Digest ◽  
1986 ◽  
Vol 35 (5) ◽  

Abstract Copper Alloy No. C86100 is a copper-zinc-aluminum-manganese-iron alloy, sometimes classified as a high-strength yellow brass. The principal strengthening element is aluminum. Its tensile strength is typically 95,000 psi (655 MPa). It has a good combination of strength and ductility along with good resistance to corrosion. Its typical uses are marine castings, gears, gun mounts, bearing and bushings. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive strength as well as fracture toughness. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Cu-510. Producer or source: Copper alloy foundries.


Alloy Digest ◽  
1975 ◽  
Vol 24 (1) ◽  

Abstract FORMALOY is a high-strength, high-purity zinc-base alloy with excellent performance in dies for forming sheet metal. It has a fine, dense grain structure which contributes markedly to its good toughness, excellent machinability and ability to develop a high polish. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive strength as well as fracture toughness. It also includes information on corrosion resistance as well as casting, forming, heat treating, machining, and joining. Filing Code: Zn-17. Producer or source: Federated Metals Corporation, ASARCO Inc..


2020 ◽  
pp. 260-266
Author(s):  
V.E. Arkhipov ◽  
T.I. Murav’eva ◽  
M.S. Pugachev ◽  
O.O. Shcherbakova

The problems of changes in the coating structure depending on the composition of the sprayed mechanical mixture using copper particles and mixture of copper and zinc particles (" brass") and the effect of structural factors on the tribological properties of the deposited metal layer are considered. The results of X-ray structural, phase, chemical and durometric analyzes, as well as tribological testing of coatings are presented. It is found that structure with hardness of ≈102.7 HV is formed in the coating from mechanical mixture of particles of copper and aluminum oxide (corundum). Numerous pores are observed in the structure of the deposited metal layer, the main size of which does not exceed 2 μm. In the coating from mechanical mixture of particles copper, zinc and aluminum oxide (corundum), structure is formed based on copper with hardness of ≈106.5 HV, zinc — ≈49.7 HV, intermetallic compounds (γ- and ε-phases) — ≈168.7 HV, the mass fraction of which is 62.0, 7.9 and 24.2 %, respectively. Both coatings can be used in sliding friction pairs.


Author(s):  
Mehdi Soltan Ali Nezhad ◽  
Sadegh Ghazvinian ◽  
Mahmoud Amirsalehi ◽  
Amir Momeni

Abstract Three steels were designed based on HSLA-100 with additional levels of Mn, Ni, Cr and Cu. The steels were prepared by controlled rolling and tempered at temperatures in range of 550–700°C. The continuous cooling time curves were shifted to longer times and lower temperatures with the increased tendency for the formation of martensite at lower cooling rates. The microstructures revealed that controlled rolling results in austenite with uniform fine grain structure. The steel with the highest amount of Mn showed the greatest strength after tempering at 750 °C. The top strength was attributed to the formation of Cu-rich particles. The steel with 1.03 wt.% Mn, tempered at 650 °C exhibited the best Charpy impact toughness at –85°C. On the other hand, the steel that contained 2.11 wt.% Mn and tempered at 700 °C showed the highest yield strength of 1 097.5 MPa (∼159 ksi) and an impact toughness of 41.6 J at –85°C.


Author(s):  
Kirstin Riener ◽  
Tino Pfalz ◽  
Florian Funcke ◽  
Gerhard Leichtfried

AbstractThe growing demand for more materials available for the LPBF-process, in particular high-strength aluminum alloys, is evident in the market. In the present work, a systematic investigation of the processability of aluminum 6182 series alloys, using LPBF, was carried out. For this purpose, the influence of process parameters, especially of enhanced preheating by heating the substrate plate during the LPBF process, on the microstructure of EN AW 6182 specimens was studied.Experiments were conducted at different preheating temperatures always using the same d-optimal design-of-experiments, the laser power, scanning speed, hatch distance, and laser focus position being varied over a wide range.It was found that the preheating temperature has the strongest impact on hot cracking. Higher temperatures result in a significantly reduced number of hot cracks in the microstructure. Moreover, an equiaxed microstructure of the specimens manufactured can be observed at preheating temperatures of 500 °C. In addition to the preheating temperature, the achievable part density is most strongly affected by the laser focus position and the laser power, whereas the hatch distance shows no discernible impact on the part density. Furthermore, neither the hatch distance nor the laser focus position shows any significant effect on hot cracking.In combination with the optimal scanning parameters, crack-free parts with a fully equiaxed grain structure and densities > 99.0% can be manufactured via LPBF at a preheating temperature of 500 °C.


2021 ◽  
pp. 5-9
Author(s):  
V. V. Akimov ◽  
◽  
A. M. Badamshin ◽  
S. N. Nesov ◽  
S. N. Povoroznyuk ◽  
...  

Using experimental methods of analysis, the morphology, elemental composition and chemical state of hard alloys of the «TiC-TiNi» system in the initial state and after various types of ion-beam treatment have been investigated. It is found that the effect of a continuous ion beam leads to an increase in the microhardness of the investigated alloys by 10–12 %. When samples are irradiated with a pulsed ion beam, as a result of destruction of surface layers, the microhardness value decreases by 20 %, as a result of which this type of modification is not preferable for alloys of the TiC-TiNi system


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