Прилагане на технология за спойване в Diamond Tools

The high hardness and excellent physical and mechanical properties of diamond make diamond tools an indispensable and effective tool for processing various hard materials. The adhesion of the matrix metal base to diamond (the encapsulation ability of the matrix) is one of the main factors affecting the service life and performance of diamond tools.

 

 

Due to the high interfacial energy between diamond and general metals and alloys, diamond particles cannot be infiltrated by general low-melting alloys and have poor adhesion. In traditional manufacturing technology, diamond particles are only embedded in the matrix metal base by the mechanical clamping force generated by the matrix shrinkage, without forming a strong chemical bond or metallurgical bond, resulting in the easy separation of diamond particles from the matrix metal base during work, greatly reducing the life and performance level of diamond tools. The utilization rate of diamond in most impregnated tools is low, and a large amount of expensive diamonds fall off and are lost in waste chips during work. Lin Zengdong and others took the lead in using diamond surface metallization technology to give diamond surfaces many new properties, such as Отлична топлинна проводимост и електрическа проводимост, добра термична стабилност, подобряват оригиналните си физически и химични свойства и подобряват тяхната мощност към метални или сплави разтвори .

 

Diamond surface metallization has attracted great attention from the diamond tool manufacturing industry at home and abroad since the 1970s. Many people are committed to the research of realizing diamond surface metallization during the sintering process, adding strong carbide metal powder to the matrix material or pre-bonding it on the diamond surface (this kind of diamond does not chemically react with the coating before heating, and can only be a diamond coating) in the hope that they can achieve chemical bonding to the diamond during the sintering process. Although the literature has demonstrated that some metals such as tungsten (unoxidized) can form a WC layer on the diamond surface at a relatively low temperature (about 800℃), from the perspective of the process used to achieve diamond surface pre-metallization, it is necessary to heat at more than 600℃under vacuum conditions for 1 hour to obtain Идеалната сила на свързване . Според условията на синтероване на често използваните понастоящем импрегнирани инструменти за рязане на диаманти е малко вероятно да генерира метализиращ слой върху диамантената повърхност, ако се нагрява на не повече от 900 градуса за около 5 минути в не-вакуум или нисък вакуум ., защото дали активните метали (TI, V, Cr, etc.) are enriched on the diamond surface or the interface reaction reaches the metallurgical bonding between the binder and the diamond, it is an atomic diffusion process. According to the temperature used for hot pressing and such a short time, this process is not sufficient. Under the solid phase sintering conditions (sometimes there is a small amount of low-strength and low-melting-point Течна фаза на метал или сплав), химическото свързване или металургичното свързване на матрицата към диаманта е много слаб или изобщо няма да се формира .

 

Предварителната метализиране на диамантената повърхност не е целта, а само една от мерките за постигане на химическо металургично свързване с Matrix metal . След като диамантът на покритие се засипа в трион (пробиване), диамантът, изложен на повърхността му the diamond and the matrix have not yet reached the level of chemical encapsulation. Therefore, even if the surface pre-metallization of the diamond is achieved, the traditional solid phase powder metallurgy sintering method cannot achieve a strong bond between the diamond and the matrix material.

 

In the late 1980s, people began to explore brazing technology for diamond tool manufacturing. The diamond surface is coated with certain transition elements (such as Ti, Cr, W, etc.), and chemically reacts with them to form carbides on the surface. Through the action of this layer of carbide, the diamond, binder, and matrix can achieve a strong chemical metallurgical bond through brazing, thereby achieving true diamond surface metallization. This is the principle of diamond brazing. It can be seen from the published patents and articles that this technology can make the maximum diamond edge value reach 2/3 of the particle size, and the tool life is increased by more than 3 times, while under normal circumstances, this value is less than 1/3, and the Допустимата стойност на ръба може да бъде получена, когато операцията за заточване на ръба достигне стабилна стойност на ръба . Следователно се очаква използването на технология за спойване да постигне силна връзка между матричния метал (Brazine) и основния материал-Diamond и стоманена матрица .