Diamond coated tool selection common sense

Before choosing and using diamond-coated tools, users must understand the following common sense about diamond-coated tools:

(1) The difference between CVD diamond coating and amorphous diamond coating

Amorphous diamond (also known as diamond-like carbon) coating is a carbon film deposited by PVD process. It has both a part of the diamond SP3 bond and a part of the carbon SP2 bond; its film forming hardness is very high, but lower than the hardness of the diamond film; its thickness is also thinner than the diamond film we usually deposit. When processing graphite, the lifetime of amorphous diamond coated tools is 2-3 times that of uncoated cemented carbide tools. In contrast, CVD diamond is a pure diamond coating deposited by CVD. The tool life when processing graphite is 12-20 times that of cemented carbide tools, which can reduce the number of tool changes and improve the reliability and accuracy of machining. consistency.

(2) Hardened steel boring cannot be processed with diamond tools

Diamond is composed of carbon atoms. When some materials are heated, they absorb carbon atoms from the diamond and form carbides in the workpiece. Iron is one of these materials. When machining iron-based materials with diamond tools, the heat generated by the friction causes the carbon atoms in the diamond to diffuse into the iron, causing the diamond coating to fail prematurely due to chemical wear. 

(3) The quality of diamond-coated tools that are reground and/or heavily coated is difficult to ensure. Since the coating generated on the tool surface is pure diamond, it takes a long time to regrind the tool with a diamond grinding wheel. In addition, the tool used to grow the diamond. The preparation process changes the chemical properties of the tool surface. Since the coating requires very precise control of this chemical property, the effect of tool recoating is difficult to guarantee. 

(4) The life of diamond coated tools varies.

As with any other tool, the life of a diamond-coated tool varies, depending on the material being machined, the feed rate and cutting speed selected, and the geometry of the workpiece. In general, diamond coated tools that process graphite have a lifespan of 10-20 times that of uncoated cemented carbide tools and, in some cases, may even be longer. This allows almost any machining task to be performed with a single tool without the need for tool change due to tool wear, avoiding machining interruptions and recalibration, making it possible to achieve unattended machining. It is also possible to achieve longer tool life in the processing of composite materials.
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It has been reported that diamond coated tools can last up to 70 times longer than uncoated cemented carbide tools when processing difficult-to-machine composites such as high-density glass fibers, carbon fibers, and G10-FR4. 

(5) Peeling of diamond coating can prevent coating peeling from being a serious problem of diamond coated tools, and is also a common problem (especially when processing materials such as carbon fiber), which leads to unpredictable tool life. In the late 1990s, interface chemistry was identified as an important factor affecting the adhesion of diamond coatings. By selecting compatible carbide chemistry, proper pretreatment techniques, and reasonable deposition conditions, it is possible to reduce or eliminate spalling of the diamond coating and achieve a stable wear pattern. Observing a normally worn diamond coated tool under a microscope, it was found that the diamond was stably worn up to the cemented carbide substrate without chipping or peeling.
 

Slip On Flanges

Slip-On flanges or SO flanges are commonly lower in price than weld-neck flanges, and to this effect are a popular choice for our customers. It is welded both inside and out to provide suffcient strength and prevent leakage. Slip-On Pipe Flanges. As made obvious by their name, these pipe flanges slip over the pipe. They're manufactured with an inside diameter that is slightly bigger than the pipe's outside diameter. These attachments are connected to the pipe via fillet weld at the top and bottom of the flange.

Slip On Plate Flanges,Slip On Flange,Class 150 Flanges,Carbon Steel Slip On Flanges

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