Preparation method of ceramic viscose cut-off tool

Abstract

The invention belongs to the technical field of a new material cut-off tool, and relates to a preparation method of a ceramic viscose cut-off tool. The technique process includes slurry preparation, blank shaping and microwave sintering; the modling uniformity and compactness of a high-performance ceramic special-shaped cutter are guaranteed by the most advanced net size liquid casting in-situ consolidation forming technology; by means of microwave sintering technology, every performance index of the material is further improved, high precision, high energy property and long-term usability of the high-performance ceramic special-shaped cutter are guaranteed; the ceramic viscose cut-off tool with high intensity and good uniformity can be prepared by the sizing agent with high solid phase content and good mobility through the net size liquid casting in-situ consolidation forming technology and a microwave sintering device; after sintering, the tool can be used only after surface polishing, thereby avoiding the grinding process after sintering; the preparation method of the ceramic viscose cut-off tool is scientific and reasonable in principle, strong in operability, low in energy consumption, few in investment, high in yield rate, low in cost, and good in using environment.

Description

Technical field: [0001] The invention belongs to the technical field of preparation of new material cutting knives, and relates to a method for preparing ceramic viscose fiber cutting knives. The special ceramic cutting knives with high reliability, strength and toughness and low cost are prepared to replace metal cutting knives. Background technique: [0002] Materials, energy and information are the pillars of modern society, and they are also the main issues that people are concerned about in the new century. The development of new materials will become a new growth point of my country's national economy, which determines or affects the development of high-tech industries to a large extent. Structural ceramics are an important part of today's materials and play an important role in national economic construction and national defense modernization. Structural ceramics have excellent properties: high hardness, good heat resistance, erosion resistance, wear resistance, low cr...

AI Technical Summary

Problems solved by technology

Structural ceramics have excellent properties: high hardness, good heat resistance, erosion resistance, wear resistance, low creep rate, and chemical corrosion resistance. They are structural materials under severe working conditions. However, the Achilles heel of structural ceramics is high brittleness and low strength; since ceramics do not have a dislocation system that can glide, when the applied energy exceeds a certain limit, structural ceramics will form new cracks Surface energy is used to consume external energy, that is, new crack surfaces are formed in the ceramic body, resulting in catastrophic damage to structural ceramics; based on this, the strengthening and toughening of ceramic materials has become the key to the research of ceramic materials. Due to the characteristics and preparation of structural ceramics Because of the technology, the traditional preparation method makes the reliability of structural ceramics poor and the manufacturing cost is high; the existing structural ceramics are optimized by the strengthening and toughening technology of nanocomposite ceramics, which can greatly improve the strength and toughness of ceramic materials at the same time , there are three mechanisms for toughening and strengthening: one is that the nanoparticles added to the micron-scale ceramic matrix inhibit the growth of the matrix grains and make the structure uniform, thereby improving the mechanical properties of the material. Nanoparticles are on the grain boundary of the matrix. Most of the nanoparticles are small in size and inert during the sintering process. At a certain temperature, the matrix particles form crystal grains with nanoparticles as the nucleus, and the nanoparticles are wrapped inside the matrix particles. Forming an inner crystal structure, there are a large number of sub-interfaces in the material. Due to the mismatch between the thermal expansion system and elastic modulus of the particles of the matrix and the nano-added particles, there will be a large residual stress at the sub-interface, and the residual stress passes through the micron particles. Passed to the grain boundary, it becomes a compressive stress that is conducive to the strengthening of the grain boundary, thereby strengthening the grain boundary, and the residual stress can also cause dislocations. The nanophase pins or accumulates dislocations, which plays a role in dispersing and hindering cracks. Reach the strengthening effect; in a smaller structural range, the stress of nanoparticles can also form microcracks, constrain the expansion of initial cracks in the material, and further refine the grains, and the particles on the grain boundaries can change the fracture mode When the intergranular crack expands close to the nanoparticles on the grain boundary, compressive shear stress is formed around the particle, and the shear stress will segregate the crack tip away from the nanoparticle, thus becoming a transgranular crack. At the same time, the grain boundary is covered by particles. The possibility of local strengthening, the transgranular fracture has a larger fracture work, so it can increase the toughness of the material compared with the intergranular fracture mode; the second is the toughening mechanism of particle bridging. The bridge at the back of the expanding crack tip forms a shield for the crack surface. If the added particles are softer, the width of the dispersion bridge in the material will be large, and the critical crack propagation distance will be large. The formed protection zone will be long and absorb the fracture energy. Also large, good toughening effect

[0003] At present, the application of structural ceramics faces the problems of high manufacturing cost and poor performance reliability. The high manufacturing cost of ceramics leads to high product prices and cannot compete with metals and their composite materials. The cost of ceramic machining almost accounts for 1-2 / 3 of the manufacturing cost, mainly because the molding of ceramic parts cannot reach the near-net size molding. In addition, the performance of ceramic materials is highly dispersed and the reliability is poor, so many fields dare not set foot in ceramic products

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