Various Applications of Machining Sapphire

Sapphire is an attractive substance, often considered a precious gemstone.  It  can be produced in comparatively large dimensions due to its inertness and therefore can be machined at high temperatures. It is often used as a material for the epitaxial deposition of Gallium and Silicon Nitride.

In the Machining Sapphire process require materials to be grounded to an appropriate size, tolerance and finely polished so that the material will be useful as planned. This process creates lots of difficulties in manufacturing challenge, it is always recommended to machine sapphire under expert supervision in order to succeed.

Industrial Applications of Sapphire: 

• It can be used for insulating substrate applications in high-frequency, high-power CMOS integrated circuits. 
• The resistance of sapphire to phosphoric or hydrofluoric acid is also significant.
• In endoscopic inspection tools, sapphire is often used as a window material.
• The fine microstructure of sapphire combined with polishing and skilled machining techniques produces cutter edges and ultra fine blade.
• Sapphire has a high degree of impact erosion, therefore it is used as a material for premium transparent watch face.
• Used in devices where corrosion resistance and high temperature is required.
• Stiffness, high hardness and single crystal structure lead to use of sapphire material in many engineering or industrial components. 
• Sapphire lenses can be used in imaging applications, laser optics, and sapphire medical optics.

Sapphire is a form of the material Alumina (Aluminium Oxide – Al2O3). It is the single crystal form of Machining alumina used in engineering ceramics. Its single crystal structure has no porosity or grain boundaries. Saphire products have a measured density, which is close to the hypothetical value of pure Alumina material.

Sapphire- An Element with Unique Properties

Sapphire is one of the most durable, hardest and scratch-resistant materials. It was first synthesized in 1902. The process of making synthetic Sapphire is called as Verneuil process. Only experts can differentiate between synthetic and natural Sapphire. It offers a broad transmission range from Ultra Violet to mid infrared wavelengths (250–4500 nm). The material is able to bear up extreme temperature changes and environmental conditions.

The most valuable color of Sapphire is a cornflower blue color, also known as Cornflower Blue Sapphire or Kashmir Sapphire. A unique type of sapphire, known as color changing Sapphire, shows various color patterns depending upon the lightening. In natural light, it is blue, but in artificial light, it is violet. Pink and yellow Sapphire has recently become very popular, and is often used in jewelry.

Sapphire mainly consists of minor inclusions of minute slender Rutile needles. These inclusions decrease the transparency and clearness of a stone and are called as silk. In dense and parallel groupings, the inclusions can actually improve by allowing polished Sapphires to exhibit asterism (a prominent star like pattern). Sapphire gems displaying asterism are called as ‘Star Sapphires’, and these are highly expensive.

It is pleochroic, displays an intense and lighter color when viewed at different angles. Some pleochroic Sapphire is purple when viewed at one angle, and blue at a different angle. Color zoning, which is created from growth layers that build up at the time of the formation of the stone, may also be present in certain Sapphires. Color zoning is certainly responsible for darker and lighter colors of Sapphire. Many Sapphire gemstones are even multicolored such as pink, blue and purple.

Machining sapphire is very complex and difficult process. Its machining requires special types of tools and techniques. An ideal machining procedure is possible only if favorable conditions are provided. Diamond tooling method is highly used in machining sapphire. It is a tough and durable element and  only natural gemstone harder than Diamond. Inspite of this, Sapphire is still subject to fracture and chipping if handled roughly.