2) In the early 1970s, mechanical alloying technology was first used to prepare dispersion strengthened superalloys. The first alloy brand developed is ma753 (ni75-cr20-c0.05-al1.5-ti2.5-(Y2O3) 0.3-surplus), and the officially produced alloy brands are dispersion strengthened nickel-based superalloys MA754 and MA6000E.
3) In 1980s, the second generation dispersion strengthened superalloys, such as MA758, MA760, MA956 and TMO-2, were introduced by International Nickel Company and Japan Institute of Metal Materials Technology, and were modified by MA754, MA6000 and TMO-2, which were gradually accepted by users. In addition to preparing superalloys, mechanical alloying technology is also widely used to prepare structural materials. Dispersion-strengthened aluminum-based alloys INCOMAP-Al902 1 and INCOMAP-Al9052 have good comprehensive properties in tensile strength, corrosion resistance, fracture toughness and fatigue resistance, and are new industrial special-shaped alloy materials. These dispersion strengthening materials have been tested on Lockheed C- 130 aircraft, and the results are very satisfactory. In addition, the strength of INCOMAP-Al905XL alloy prepared by mechanical alloying technology is similar to that of 7075-T73 aluminum alloy, but the density is reduced by 8% and the stiffness is increased by 15%.
4). 1975 Jangg and others put forward a method similar to "reactive ball milling", that is, chemical additives and metal powder are ball milled together to induce a low-temperature chemical reaction and generate uniformly distributed dispersed particles. The room temperature mechanical properties and electrical conductivity of the dispersed aluminum alloy (Al-al4c 3-al2o 3) prepared by this method are better than those of SAP (dispersion strengthened sintered aluminum), and the mechanically alloyed dispersed aluminum alloy has been widely used. Dispersion strengthened copper alloy prepared by mechanical alloying technology has excellent mechanical properties. Mechanical alloying dispersion strengthened copper alloy can replace dispersion strengthened copper alloy prepared by internal oxidation method, and it is an ideal lead frame and electrode material. In recent years, the research of mechanical alloying dispersion strengthened titanium alloy, nickel alloy and molybdenum alloy and mechanical alloying dispersion strengthened intermetallic compounds is increasing, and it is estimated that more new dispersion strengthened materials will come out.
5) From the early 1970s to the early 1980s, mechanical alloying technology was mainly used to develop dispersion strengthened alloy materials. Although in 1979, White was the first to suggest that mechanical alloying may lead to amorphization of Nb3Sn superconducting materials. The former Soviet scholar Ermakov and others obtained the amorphous alloy for the first time when the Y-Co intermetallic compound was mechanically ball-milled in 198 1 year, but these two important results did not attract enough attention from the material science community at that time. Until 1983, Yeh et al. found that hydrogenation led to the amorphization of Zr3Rh. Schwarz et al. found that the solid diffusion between La and Au crystals led to amorphization. Koch et al. prepared the amorphous alloy of Ni40Nb60 by mechanical alloying, Schwarz et al. predicted the formation region of amorphous alloy of Ni-Ti binary system by thermodynamic method in 1985, and explained the formation mechanism of amorphous state by solid-state reaction theory, which made materials scientists interested in the method of preparing amorphous powder by mechanical alloying. The method of preparing amorphous by mechanical alloying has many advantages, such as obtaining more uniform single-phase amorphous and synthesizing amorphous alloys that cannot be prepared by rapid solidification technology. Because it avoids the strict requirements of metallic glass formation on melt cooling rate and nucleation conditions. The method of preparing amorphous materials by mechanical alloying has made great progress in the past twenty years.
6). Just as people use the solid-state reaction theory to find new amorphous alloys, Gaffet et al. reported that Si was partially amorphous during ball milling. This is the first example of amorphization of pure elements by mechanical ball milling. The phenomenon that pure elemental powder and pure compound powder form amorphous by mechanical alloying cannot be explained by solid state reaction theory. Materials scientists then ball-mill more than two kinds of elemental powders (including two kinds of elemental powders), and the process of obtaining non-equilibrium phase through solid phase diffusion is called mechanical alloying, while the process of ball-milling single element or single compound powder to obtain non-equilibrium phase without transferring substances is called mechanical grinding (MG or MM for short). Obviously, their amorphization mechanisms are different.
7). Quasicrystal is a new material discovered by Schechtman et al. in quenched Al-Mn alloy in 1984, which has aroused great interest in the field of materials. Many methods can be used to prepare quasicrystal alloys, such as rapid condensation, sputtering, vapor deposition, ion beam mixing, heat treatment of amorphous phase, solid diffusion reaction and casting. The preparation of quasicrystal alloys by mechanical alloying technology is one of the important advances in mechanical alloying research. Ivanov et al. prepared icosahedral quasicrystals of Mg3Zn(5-x)Alx (where x=2~4) and Mg32Cu8Al4 1 by mechanical alloying technology, and their structures are the same as those prepared by rapid cooling technology. Eckert et al. also observed that the metal powder with the composition ratio of Al65Cu20Mn 15 formed icosahedral quasicrystal phase after mechanical alloying.
8). Solid solution can be formed by mechanical alloying of component metal powders of alloy system, which are completely miscible in solid state. Benjamin mechanically alloyed nickel powder and chromium powder in 1976, and found that atomic-scale alloying can be realized. He found that the magnetic properties of Ni-Cr alloy prepared by mechanical alloying method are exactly the same as those of Ni-Cr alloy with the same composition prepared by traditional ingot metallurgy method. Si and Ge are completely soluble in each other, but they are both brittle materials at room temperature. The experiment of Davis et al. in 1987 shows that when Si and Ge powders are mechanically alloyed, the lattice constants of Si and Ge gradually approach, and when the milling time reaches 4~5 hours, the lattice constants merge into one, which indicates that Si-Ge solid solution is formed.
9) Non-equilibrium processing methods, such as rapid solidification, can break through the equilibrium solid solubility limit of alloys, and mechanical alloying technology has the same effect. In 1985, Schwarz et al. found that the solid solubility of Ti in face-centered cubic structure Ni was as high as 28mass% in mechanically alloyed titanium and nickel powder, while according to the equilibrium phase diagram of Ti-Ni alloy, the solid solubility of Ti in Ni was only a few percent. In 1990, Polkin and others systematically reported the increase of solid solubility caused by mechanical alloying, and they found that the solid solubility expanded obviously in the alloy systems studied, such as Al-Fe, Ni-Al, Ni-W and Ni-Cr.
10). Generally speaking, ordered solid solution can produce disordered structure through radiation, rapid solidification, large plastic deformation and other processes, and lead to changes in alloy properties. Mechanical alloying can also lead to disorder of ordered alloys and intermetallic compounds. The first report is that Ermakov et al. disordered the ordered compound ZnFe2O4 by mechanical grinding (MM). 1983 Elsukov et al reported that Fe3Si phase was disordered due to mechanical alloying. Bakker et al. reported the detailed research results on the disorder of intermetallic compounds.
1 1). Mechanical alloying is one of the few methods to uniformly mix two or more immiscible phases. In fact, this is the case with dispersion strengthened alloys, because oxides are basically immiscible with the metal matrix. More generally, mechanical alloying can be applied to binary alloy systems that are immiscible in solids or even liquids. Benjamin introduced the results that Fe-50m s% Cu alloy with limited mutual solubility and Cu-Pb alloy with immiscible gap formed uniform compounds in liquid during mechanical alloying. Green et al. prepared a new electrical contact material by mechanical alloying. The original material is a mixture of Cu- 1.5 vol% Ru, and Cu and Ru are immiscible. Cu-Ru composite material is obtained by mechanically alloying mixed powder of Cu and Ru, then annealing, cold pressing and hot rolling, and the strip with final size is obtained by cold rolling and annealing. The SEM results show that the final diameter of Ru particles is1~ 2 μ m. If Cu is removed from the surface of the strip by etching, hard, refractory and conductive Ru particles will protrude from the surface, which can be used as electrical contacts, and the Cu matrix plays a supporting role to ensure the continuity of current.
12). The preparation of nano-materials is one of the research hotspots in the field of materials science. Nano-materials have obvious volume effect, surface effect and interface effect, which cause changes in mechanical, electrical, magnetic, thermal, optical and chemical properties of materials. There are three main methods to prepare nanocrystalline materials: solid phase method, liquid phase method and gas phase method. Thompson et al. first reported the synthesis of nanocrystalline materials by mechanical alloying in 1987. Hellstern et al. and Jang et al. reported that nanocrystalline materials were prepared by mechanical alloying technology with elemental powder and intermetallic compound powder. Schlump et al. found that nano-sized dispersed phase particles can be generated by ball milling in immiscible alloy systems such as Fe-W, Cu-Ta, Ti-Ni-C and W-Ni-C.
13). 1988 Professor Shinomiya of Kyoto University in Japan and others systematically reported the preparation of Al-Fe nanocrystalline materials by high-energy ball milling, which found a feasible way for the preparation and application of nanocrystalline materials. The research shows that nanocrystalline materials can be synthesized by ball milling of elemental powder, intermetallic compound powder and immiscible alloy powder. At present, nanocrystals have been obtained in pure metal powders such as iron, chromium, niobium, tungsten, zirconium, hafnium and ruthenium. Nanostructured solid solutions were obtained in Ag-Cu, Al-Fe and Fe-Cu alloys. Metastable phases with nanostructures were obtained in Cu-Ta and Cu-W alloys. Nanocrystalline intermetallic compounds have been obtained in Fe-B, Ti-S, Ti-B, Ni-Si, V-C, W-C, Si-C, Pd-Si, Ni-Mo, Ni-Al and Ni-Zr alloys.
14). From the early 1980s to the early 1990s, mechanical alloying technology was mainly used to prepare non-equilibrium materials, and almost all non-equilibrium materials can be prepared by mechanical alloying technology. The research on the preparation of non-equilibrium materials makes the research on mechanical alloying technology set off another climax.
15). Many alloys can be synthesized into intermetallic compounds by mechanical alloying. Because the cast intermetallic compound usually has a coarse-grained as-cast structure with poor machinability, it is difficult to control its microstructure even by deformation-heat treatment technology. Therefore, it is hoped that the intermetallic compound prepared by mechanical alloying technology is a kind of material with microcrystalline and nanocrystalline structure, which can improve the brittleness of intermetallic compound. Mcdermott et al. first prepared intermetallic compounds by mechanical alloying. They mixed zinc powder and copper powder in a certain proportion, and then ball-milled to obtain β brass. Ivanov prepared the intermetallic compound Ni2Al3 by ball milling the mixture of Ni powder and Al powder according to the composition of Ni40Al60. Usually, it takes a long time to prepare intermetallic compounds by mechanical alloying, which affects the preparation of intermetallic compounds. Since Schaefer and others. In 1989, it is found that some metals can be reduced from their oxides by self-propagating combustion induced by mechanical alloying. In 1990, Atzmon and others found that self-propagating combustion occurred during ball milling of Ni powder and al powder, and the self-propagating combustion synthesis reaction of mechanical alloying became a research hotspot. This self-propagating combustion reaction can greatly shorten the ball milling time and prepare various intermetallic compounds.