Machine parts The vast majority is made of carbon and alloy structural steel, turning these materials, multi-ribbon cuttings. Removed from the rough on the chip, blades need to bear a huge load has been removed from the blades of the rake face of the chip to slide rapidly, its relative movement with the blade, resulting in the formation of intense friction surface temperature, so should not only blade material Wear-resistant, but also to high temperature, to maintain hardness at high temperatures. Therefore, cutting of such materials should be used with TiC + TaC larger proportion of P type carbide. Today to improve the cutting efficiency; cutting speed; feed rate higher and higher, P type carbide blade can not do. In the last century, it developed in the P class of rigid blade and then deposited a layer of high hardness on the membrane, called coated (coating). Coating thickness of only about 0.2% of blade thickness, they can greatly enhance the blade life, and can adapt to the higher cutting speed. Over the past decades coating technology has also been developed, such as from the developed to the multi-layer or single layer nano-multilayers; thickness of a few μm to more than a dozen μm, or even more types of coating material properties and deposition technology more and more advanced; as matrix material from a single isotropic carbide is also developed to meet the processing requirements of the performance of a tilted structure.
This is the maximum number of materials for the machining requirements, Mitsubishi, through years of research and development, has successfully launched a new series of blade material UE.
succinctly expressed the UE series of composition, the selection of the various grades as well as their concept map. In Y axis can be the table cut depth (back to eat knife volume), the abscissa the table feed. Coordinate origin can be seen in the vicinity of the gap at the circle, saying along the 45-degree line in the vicinity of various depths of cut and feed rate of the cutting conditions, carrying out minor intermittent cutting, the recommended selection of specific grades UE series of tools at the same time may elect the corresponding chip-breaker. For example, when a smaller depth of cut and feed, they can choose UE6010 with the SH chip-breaker, if the depth of cut and feed rate generally increases upward along the 45-degree line, indicating a gradual increase in cross-sectional area of the chip, cutting load gradually increases, , followed by optional UE6010 materials and MV, and GH chip-breaker, when cutting a larger, they can choose UE6020 materials and Hx chip-breaker. If there is no groove on the workpiece, gaps, etc., at this time is called a continuous cutting cutting, even if the machining allowance is also not cutting the workpiece surface, but cutting the inner layer, while if the higher parts of the installation of rigid and difficult to produce vibration, cutting force at this time roughly constant, the above conditions are stable under the cutting cutting the scope of the top left of Figure 1. In this context, the cutting, with the depth of cut and feed rate increases, respectively choose UE6005 materials and SH, MV, GH chip-breaker, when the depth of cut and feed rate when a greater choice of materials and Hx-off UE6010 flute. Figure 1 lower right corner there is a gap with a four round workpiece image to express the gap formed when the multi-processing of more intense intermittent cutting. Machining allowance uneven, non-inner cutting the workpiece but high hardness and uniformity of the skin without cutting or the installation of poor rigidity workpiece easy to vibration cutting, the cutting areas are considered unstable at this time can mainly be selected UE6020 material , with the depth of cut and feed rate of increase may be the same pre-select the appropriate chip-breaker. Unstable conditions even in severe cases should be selected UE6035 and the corresponding chip-breaker. Why do I choose? Due to UE series, these four materials, respectively, in Figure 1 is equivalent to ISO international standards, from P01 to P40 of the different levels above the higher the number the smaller the hardness of the table, the more wear, the more can be adapted to the higher cutting speed, number of the more The higher toughness large table, the more resistant to shock, but the relatively low cutting speed of adaptation, which, under the right in Figure 1 Recommended cutting conditions can be seen.
In explaining the characteristics of UE series before a brief description of what the tool failure injury problems. Today carbide tool materials, metal ceramic, ceramic, CBN (Fang boron nitride), PCD (polycrystalline diamond man-made), etc.-based sintered materials, high-speed steel usage has declined. Sintered materials, the damage morphology and high-speed steel as a wear (Wear), wear and tear damage is a progressive and cutting time, cutting the length of the relevant. Because it also has its own characteristics of sintered materials, namely, hard and brittle, lack of toughness, in the cutting process will be a result of cutting force, cutting heat caused by the change instantaneous and low-cycle impact, while the formation of brittle damage (Brittle Fracture), the performance of this damage (1) to the knife's edge, said some small gaps or slight defect in collapse (Chipping). (2) have a big gap in serious damage or collapse, said a knife (Broken Fracture). A small gap appeared on the blade, or defect, it can not then do finishing, but in some cases, may continue to do so rough use. (3) In addition, in the processing, some chip bonding (Adhesion) fused (Welding) where they are needed in the vicinity. General bonding, sintering wear is part of non-sintered tool damage one of the reasons right there in terms of sintered tool material may have bonding, sintering wear, but more important is the tool the surface of the chip stick firmly together knot, fused objects, BUE being processed subsequent attacks, forcing it to the surface of separation of the tool, in this process, the separated part of the material while also taking with knives causing bonding, sintering defect and damaged, it is processed in the field should try to avoid chip bonding fused. Of course, they also affect the processing of surface quality. (4) The poor thermal conductivity of sintered materials, easy to produce thermal crack damage.
Mitsubishi UE series of coating material is as good resistance to the main tool of these injuries, to ensure efficient processing of long life out developed. UE series of these four coatings are used CVD (chemical vapor deposition method) is made, this method thick films can be obtained, wear, high temperature, can be adapted to high speed and large feed, large depth of cut machining. UE series of four coating for UE6010, UE6020 applications most widely used. The most universal and typical. Figure 2 shows the organizational structure of images UE6010 and UE6020.
We can see from Figure 1, in the 45-degree line, as the first recommendation is UE6010, because they have a very high hardness is also quite resilient wear can adapt to a certain degree of intermittent cutting and impact, and its matrix alloy is tilted structure, namely, the performance function of each layer is different, and the combination of the top coating toughness large to ensure that coating can be firmly combined with its resistance, defects and damage, the Department of the matrix alloy while doing hard core, anti - deformation ability. Coating is divided into three layers, with the substrate is the most inner TiCN columnar crystal fibers, sub-layer of high hardness and toughness are also considerable, can well before and after the flank wear resistance.
An intermediate layer of fine grain size Al2O3, its hardness up to HY2100, the free energy of formation value of -100Kcal/g.atom This value represents the chemical stability, the smaller the value of the better chemical stability, heat resistance, the better the , there is this layer of high-speed cutting is unlikely to generate tool and workpiece materials, the proliferation of molecules with each other, resulting in the flow of ribbon cuttings caused by the former Crater flank wear, this layer at high temperature melting of iron under conditions of almost zero degree, so easy to fused iron filings in its surface, and thus to avoid the resulting injuries. It is a unique smooth coating technology (even coating technology) painted surface, particularly smooth surface, on this basis, and then coated with a layer of a special titanium compounds, this layer to maintain smooth, so that the friction coefficient decreased to further reduce the iron filings in bonded fused. Because it is golden yellow, easier to find minor damage that may arise. In recommending selection UE6010 when specially recommended cutting conditions suitable for a wide range of MV chip-breaker, this wonderful combination of both, but also to increase its versatility. UE6020 structure and performance characteristics of each layer and the substrate alloy structural properties UE6010 roughly the same. But the thinner film hardness lower than the UE6010, poor wear resistance, the adaptation cutting speed is also lower but the recommended cutting speed range can still maintain a very high wear resistance. Its bending strength, toughness and impact resistance is higher than UE6010, suitable for cutting within the cutting of instability. The shock loads, thick film may rupture failure, decline in the credibility of the film, thick layer of credibility is more resistant to high impact.
UE6010 and UE6020 for the use of conditions, such as in continuous cutting, very stable cutting conditions, the hardness could be further selected higher and more durable UE6005, little or no impact load at this time, we can recommend a higher cutting speed according to Yi to achieve more efficient cutting. On the contrary, if intermittent cutting, impact load larger, you can choose more than UE6020 toughness, flexural strength greater UE6035, the recommended cutting speed in the work, although the rate decreased , but avoids the knife defects, damage, so that to extend the tool life to avoid frequent replacement blade, shortening the time support is also improved cutting efficiency.
本文转自：China Industry News
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