2results about How to "Remarkable grain refinement effect" patented technology

The application discloses an in-situ self-generating ceramic particle reinforced low-tungsten-content composite material, and a preparation method of the in-situ self-generating ceramic particle reinforced low-tungsten-content composite material.The low-tungsten-content composite material is composed of the following components in percentage by mass: W 59% to 69%, Ni 21% to 28%, Fe 9% to 12%, and ceramic reinforcing phase 1%.The tungsten content in the material system is greatly reduced, the toughness of the bonding phase is significantly increased, the plasticity and processing performance are improved, the W atoms in the bonding phase are difficult to diffuse to the surface of other W grains during the sintering process, the long-range migration is blocked, the W grain growth is effectively inhibited, the size of the in-situ generated ceramic particles is small, the distribution is uniform, the interface between the metal matrix and the ceramic particles is pure and firm, the strong dispersion strengthening and fine-grain strengthening effects can be produced, and the application of the low-tungsten-content composite material is suitable for the fields of aerospace, radiation shielding and precision instruments.

The present application belongs to the field of light metal plastic forming, and particularly relates to a device and method for preparing fine-grained magnesium alloy rod by asymmetric multi-directional shear extrusion. The wedge block combination in the present application can combine multi-directional shear extrusion deformation and differential speed torsional deformation, effectively weaken the magnesium alloy basal plane texture, and improve the mechanical properties of the magnesium alloy. While the magnesium alloy material is subjected to torsional extrusion in the torsional extrusion deformation zone, the sectional area of the channel gradually decreases, and the angle of the channel deflection is different, so that the frictional force of the magnesium alloy material on the surface of the convex and concave dies at the contact position is different, and the degree of torsional deformation is also different, so that the material realizes differential speed torsional deformation, and the grain refinement effect of the magnesium alloy rod is more remarkable. When the magnesium alloy material passes through the large and small concave dies, the deformation degrees of the magnesium alloy material are different due to the particularity of the structure, so that the grain refinement is effectively realized. At the same time, the flowability of the magnesium alloy material is also different, causing differential speed flow to deflect the c-axis, thereby weakening the texture.