
Courtesy of Argonne National Laboratory
Award-winning grids and collimators produce better X-ray and nuclear images
The dental industry has recently started using the term Galvanoforming electroforming in which gold and ceramics are used to produce aesthetically good looking teeth restorations. The galvanoforming process takes place through using gold sulphite baths in gold concentrations between 40 and 60 g/l (gram per liter).
The metal deposited and which is built up by galvanoforming to a three-dimensional moulding can fundamentally be any random metal which can be deposited from an electroplating bath. In the present case mainly the metals which can be deposited in dentistry are used. Particular reference is made in the series of non-ferrous metals to nickel, chromium, cobalt and molybdenum, which are used for dental materials such as NiCr-alloys, Ni-based alloys and CrCoMo-alloys. Preferably with the method according to the invention deposition takes place of a precious metal or a precious metal alloy. These can in particular be metals from the platinum group and silver. In particular, (pure) gold or a gold alloy are deposited.In electroforming, master mandrels can be photo chemically etched precision templates made out of stainless steel or in the case of a temporary mandrel form, they are etched out of aluminum. The master mandrel is then placed into a special tank for electro deposition, usually of a nickel or copper based solution. Electroforming differs substantially from electroplating in that the formed object is much thicker and is typically a self supporting structure. Once the desired amount of thickness of metal is achieved over the mandrel, typically a matter of minutes to hours in the electroforming chemical plating bath, the mandrel is removed and separated from the formed object. This metal object is a free standing product that is an exact representation of the original master template, including the finished surfaces of the original mandrel.
Galvanic deposition in the case of the method according to the invention normally takes place from a so-called galvanizing or electroplating bath, which contains in an adequate concentration the metal or metals to be deposited. The metal or metals to be deposited are present in the form of complexes. The baths also contain conventional additives such as deposition aids, brightening agents, etc.
See: Method for producing prosthetic moulded parts for dental use
It has been reported that the capabilities of eforming provide for tolerances of 1.5 to 3 nanometers and is ideal for micro-machining of precision metal parts.
Some of the eformed products include micro mesh, ultra precision sieves, shadow masks, encoders, and seamless three-dimensional parts such as reflectors, belts, and cylinders for all types of industries.
When electroforming an object, it is important to start off with a precision part. This is where the beauty of photo chemical machining comes in. The process of using photo etching or photo chemical machining for fabricating complex metal parts, with intricate shapes, flanges, bosses, parabolas, ellipses, conicals, and precision tolerances makes it easy for duplicating these metal parts and ideal for using them as mandrel forms for the final eforming process.
Contact E-FAB for a quote on precision photo etched mandrels. Note also, that many times precision thin metal parts of complex and compound geometries can be totally fabricated using the photo etching and photochemical machining process. It all depends on the various applications and part tolerances required of having to use electroforming or the photoetching method. E-FAB provides engineering and customer support for all types of OEM products. Visit E-FAB and talk with a sales consultant or an engineer to get your engineering and technical questions answered today.