Sandvik Coromant technology application of direct pressing sintering

572Hits2014-01-10 08:12:02　Source:Sandvik Coromant

In recent years, composite materials in the drilling tool, to discuss the most is directly pressed sintering PCD tool innovation technology.To understand this concept, first need to understand the limitations of PCD and before.Generally speaking, in the attached flat sheet of PCD and cemented carbide layer in the production of cutting tools, PCD in brazing welding on the cutter blade.

This approach has two shortcomings: 1. The machining cutter groove constrained, because it is a flat piece of production;2. The flat piece of welding in cutting tools of copper welding head is apart from the cutting edges are very close.If the temperature is close to the melting point of brazing, heat processing, can make the welded joint failure.

　　Strategic positioning

In order to overcome these shortcomings, and make full use of the advantages of PCD, sandvik coromant and Precorp studying, adopting direct pressing sintering technology of PCD material, strategically focused on manufacturing PCD tool blank.To make this kind of knife billet, the diamond powder into carbide cutter blade on the open slot, diamond and carbide under high temperature/high pressure sintering becomes an organic whole, sintering good tool blank in brazing welding on the handle.Finally in accordance with the requirements for the design of the cutter blade, cutter blade machining precision.

For processing workshop, it is a good news, because of the characteristics of sintering PCD can make accurate positioning PCD blade when cutting tool machining.In addition, still can be accurately made spiral cutting edge or other complex blade, it is in the use of welding between PCD were unable to do it.Sintering PCD technology for sandvik coromant provides design optimization cutting blade, the optimization of the blade shape rigid set can be adapted to owe, can adapt to stable high-volume processing precision.Using PCD direct pressing sintering technology, but also can solve the problem of the copper welding head failure.Admittedly, there is still a copper welding head pressing sintering the tool - it just located above the handle partial position, far from cutting parts, not affected by heat.

　　Special cutting tool edge shape

Generally speaking, the direct pressing sintering PCD cutting tool with a sharp cutting edges, even in the processing of abrasive wear resistance of the largest composite material, can maintain a sharp edge.This technique can be even further strengthen, such as strengthening the rounded part of the cutting tool, in order to improve the cutting speed, without affecting the surface quality and dimension tolerance.

For processing laminated composite materials and metal materials, direct pressing sintering PCD cutting tool can be used in a micro grinding technology, so that the processing of high stress concentration parts, also help keep the sharpness, extend the service life of cutter.Knives sharp cutting edge synthetic fiber, need the thrust of small, can be processing defects (such as layer, base material melting/softening, fiber pull out and surface burning) reduced to a minimum.

　　driving mechanism

Composite materials and parts processing technology, the machining continue to dominate.In the aviation industry, for example, in preparation for installation of composite frame and parts of fasteners, it takes a lot of time.Even using the latest reduces the assembly requirements of the unified structure, from the perspective of the machining efficiency and cost of drilling is still the dominant factor.

Sandvik coromant PCD insert, adopting direct pressing sintering technology, cutting edge can be made into all kinds of groove type, minimizing the in and out of the hole location of the stratified tendency, but the application method is still a tool selection of a major factor.For example, using the automatic feeding device, direct pressing sintering PCD bit (for example 85 or 86 PT series CD10), USES the PCD insert protection design, increases the stability of machining process.At this point, the cutting tool PCD insert part layer, shorten the PCD exposed portion of the total length.Can help to prevent cutting edge split, so as to prolong the service life of cutting tools.These bits also can be used in cold way, this way is particularly recommended for machining aluminum alloy stack and/or titanium alloy composite material.

　  CNC lathe

CFRP on the fixed bed CNC machine tool parts machining, we already have another CD10 direct pressing sintering PCD bit, CoroDrill ® 859 v is optimized, M21E, for example, can be used for one-way belt material and epoxy resin and BMI (maleic imide) resin.This bit has a sharp blade double Angle, can reduce stratification, in CFRP with coating (such as glass fiber and copper) drilling, performance is also very good.

Using titanium alloy stack of carbon fiber is one of the most difficult machining material combination, but sandvik coromant and Precorp together, overcome difficult, improves the machining efficiency of such materials.For the performance of direct pressing sintering PCD CoroDrill ideas, use 15 mm thick CFRP sandwich, 10 mm titanium alloy plate, when the drill hole, the cutting speed for about 12 m/min, feeding is 0.05 mm/rev.

　　Once drilling

Processing for CFRP (carbon fiber reinforced plastic) or CFRP material/metal stack to shorten downtime and to improve the surface quality of hole and pore size error, the drill tip configuration is optimized using the direct pressing sintering technology of PCD bit and optimize the processing technology is of vital importance.Although people want to use the one-time finish drilling tool to shorten production time, but when requires high precision, the need when drilling twice or three times in the operation, namely pre drilling, drilling and ream.

Although it has been thought to want to drilling in composite materials, with stable, reliable and repeatable once completed drilling process is a difficult thing, but this kind of idea is about to change.Sandvik coromant is a large number of trials, to aviation parts during drilling, shorten processing time, reduce the tool using the number.These tests focus on a single complete drilling process, the dynamic type feeding machine, drill through aluminum/titanium alloy of CFRP materials (CFRP/Ti/Alu).For large aerospace manufacturing test results for the first time, see the hope, borehole quality can fully meet the desired level of demand.

　　Direct pressing sintering PCD technology helped sandvik coromant meet the needs of such company, developed a dedicated channel, to adapt to the needs of different materials with different conditions.

　However, direct pressing sintering PCD cutting tool is not only used for machining, can also be used for the surface and edge machining process.Is a typical instance, vertical tail plane made of composite material, the edge of the material and processing difficulty is quite large.However, using PCD direct pressing sintering technology CoroMill ® Plura vertical milling cutter is most suitable for this kind of processing, thus reducing fiber fracture phenomenon, increase the metal removal rate.

　　From the Angle of the composite material processing capacity and reduce the cost analysis, PCD direct pressing sintering technology undoubtedly is the biggest driving force, for a variety of applications, has great potential and competitive advantage.