Successful Application of PCD Direct Sintering Technology

In recent years, composite tool drilling tools, the most discussed tool innovation is PCD direct suppression sintering technology. To understand this concept, first of all need to understand the PCD and its previous limitations. In general, PCD is attached to the cemented carbide layer. When the cutting tool is made, the PCD is welded to the tool body by brazing.

This method has two major shortcomings: 1. Tool groove processing is limited, because it is made of flat film; 2. The flat sheet welded to the cutting edge of the tool from the cutting edge is very close. If the temperature is close to the melting point of the brazing, then the heat generated during processing will cause the welded joint to fail.

Strategic Positioning

In order to overcome these shortcomings, and make full use of the advantages of PCD, PCD material using direct compression sintering technology, from the strategic focus on manufacturing PCD tool blank. When the cutter is made, the diamond powder is put into the slot opened in the carbide tool cutter body, and the diamond and the cemented carbide are sintered at high temperature and high pressure. The sintered tool blank is welded by brazing On the handle. And ultimately in accordance with the requirements of the blade shape design, precision tool blade processing.

For the processing plant, this is a good news, because the characteristics of sintering PCD, can make the tool in the positioning of the PCD blade accurately. In addition, the spiral cutting edge or other complex blade type can be precisely made, which can not be achieved when using a PCD sheet. This optimized blade shape can be adapted to less rigid settings, but also to adapt to precision and stable mass processing. PCD direct suppression of sintering technology, but also to solve the problem of failure of the brazing joint. It is true that direct pressing of sintered knives still has brazed joints - this is only located above the shank side, away from the cutting site, free from heat.

Special tool blade type

In general, PCD direct suppression of sintered knives has a sharp cutting edge type, even in the processing of abrasive wear resistance of the largest composite material, but also to maintain a sharp edge. This technique can even be further enhanced, for example, by strengthening the fillet portion of the tool to increase the cutting speed without affecting the surface quality or dimensional tolerances.

For the processing of composite materials and metal laminated materials, PCD direct compression sintering tool can be used micro-grinding technology, in order to process high stress concentration, but also help to maintain the sharpness and extend tool life. Tool sharp cutting edge cutting synthetic fibers, the required thrust is small, can be processing defects (such as delamination, substrate melting / softening, fiber extraction and surface scorching) to a minimum.

Core driving force

Composite materials and parts processing technology, the hole processing continues to dominate. For example, in the aerospace industry, it takes a lot of time to prepare fasteners for composite racks and parts. Even with the latest unified structure that reduces assembly requirements, drilling is still the dominant factor in terms of processing efficiency and cost.

PCD drill bit with direct compression sintering technology, cutting edge can be made into a variety of groove, the hole into the hole position to minimize the tendency, but the application method is still a major factor in tool selection. For example, when using the automatic feed device, the PCD directly suppresses the sintered bit (eg 85 or 86 PT series CD10) and uses the PCD blade protection design to increase the stability of the process. At this point, in the cutting tool PCD edge part of the added protective layer, shortening the PCD exposed part of the total length. This prevents the cutting edge from cracking, thereby extending the tool life. These drills can also be used in the internal cooling mode, which is particularly recommended for the processing of aluminum alloy and / or titanium alloy stack of composite materials.

Drilling once

In order to shorten the downtime and to improve the surface quality and aperture error of the CFRP (carbon fiber reinforced plastic) or CFRP / metal stacking material, it is important to use the direct compression sintering technology to optimize the drill tip configuration PCD drill bits and optimize the machining process of. Although it is desirable to use a one-time drilling tool to shorten the production time, two times or three operations, drilling, drilling and reaming, are required for drilling when high accuracy is required.

PCD direct suppression sintering tool is not only used for hole processing, can also be used for surface processing and edge processing processes. A typical example is the vertical tail of the aircraft made of composite material, which is difficult to process at the edges of this material. However, CoroMill? Plura end mills with PCD direct sintering technology are best suited for this process, reducing fiber fragmentation and increasing metal removal.

From the perspective of composite material processing capacity and cost reduction, PCD direct sintering technology is undoubtedly the biggest technical driving force, for all applications, have great potential and competitive advantage