Joining processes:

Metal joining is a controlled process used to fuse metals. There are several techniques of metal joining of which welding is one of the more basic forms.

Metal joining is also include Brazing, Soldering and Riveting process.

Welding:

Welding is a fabrication process that joins materials by causing coalescence. This is often done by melting the

Work pieces and adding a filler material to form a pool of molten material (the weld pool) that cools to become a strong joint, with pressure sometimes used in conjunction with heat, or by itself, to produce the weld.

Brazing:

Brazing is a process for joining similar or dissimilar metals using a filler metal that typically includes a base of copper combined with silver, nickel, zinc or phosphorus. Brazing covers a temperature range of 450ºF -(Brazing differs from welding in that brazing does not melt the base metals.

Soldering:

Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal (solder) into the joint, the filler metal having a lower melting point than the adjoining metal.

Riveting:

A rivet is essentially a two-headed and unthreaded bolt which holds two other pieces of metal together. Holes are drilled or punched through the two pieces of metal to be joined. The holes being aligned, a rivet is passed through the holes and permanent heads are formed onto the ends of the rivet utilizing hammers and forming dies (by either cold working or hot working).

Cutting processes:

Cutting is a collection of processes where in material is brought to a specified geometry by removing excess material using various kinds of tooling to leave a finished part that meets specifications.

 

Milling:

Milling is the complex shaping of metal or other materials by removing material to form the final shape. It is generally done on a milling machine, a power-driven machine that in its basic form consists of a milling cutter that rotates about the spindle axis (like a drill), and a worktable that can move in multiple directions.

Turning:

Turning is a metal cutting process for producing a cylindrical surface with a single point tool. The work piece is rotated on a spindle and the cutting tool is fed into it radically, axially or both

Threading:

There are many threading processes including: cutting threads with a tap or die, thread milling, single-point thread cutting, thread rolling and forming, and thread grinding. Usually threads are produced on lathe machain.

Grinding:

Grinding uses an abrasive process to remove material from the work piece. A grinding machine is a machine tool used for producing very fine finishes, making very light cuts, or high precision forms using an abrasive wheel as the cutting device.

Filling:

Filing is combination of grinding and saw tooth cutting using a file. Prior to the development of modern machining equipment it provided a relatively accurate means for the production of small parts, especially those with flat surfaces.

Surface treatment:

Surface finishing is a broad range of industrial processes that alter the surface of a manufactured item to achieve a certain property.

Case hardening:

Case hardening is specified by hardness and case depth. The case depth can be specified in two ways: total case depth or effective case depth. The total case depth is the true depth of the case.

Mechanical hardening:

Peening is the process of working a metal's surface to improve its material properties, usually by mechanical means such as hammer blows, by blasting with shot or blasts of light beams with laser peening. Peening is normally a cold work process being a notable exception.

Chemical vapor deposition

Chemical vapor deposition (CVD) is a chemical process used to produce high-purity, high-performance solid materials. The process is often used in the semiconductor industry to produce thin films. In typical CVD, the wafer is exposed to one or more volatile precursors, which react and/or decompose on the substrate surface to produce the desired deposit. Frequently, volatile by-products are also produced, which are removed by gas flow through the reaction chamber.

Thermal spraying

Thermal spraying, a group of coating processes in which finely divided metallic or nonmetallic materials are deposited in a molten or semi molten condition to form a coating. The coating material may be in the form of powder, ceramic-rod, wire, or molten materials.

Electroplating

Electroplating is a process that uses electrical

current to reduce dissolved metal cations so

that they form a coherent metal coating on an

electrode. The term is also used for electrical

oxidation of anions onto a solid substrate, as in

the formation silver chloride on silver wire to

make silver/silver-chloride electrodes

Anodizing:

Anodizing is an electrochemical process that converts the metal surface into a decorative, durable, corrosion-resistant, anodic oxide finish. Aluminum is ideally suited to anodizing, although other nonferrous metals, such as magnesium and titanium, also can be anodized.

Painting:

There are painting used for surface decorations, anti-rusting and anti-corrosion. Recently, functional painting such as electro-conductive painting, non-adhesive painting, and lubricating painting are in active uses.

Types of Paint for Metal

Spray Paints Oil-Based Paints

Acrylic Latex Paint Metallic Paints

Spray Paints

Spray paints are highly versatile products that are suitable for use on metal, wood and plastic. Often spray paints are convenient to use and can save a painter time by simply spraying the surface of your object and getting complete coverage without the use of paintbrushes and other painting accessories..

Oil-Based Paints

Though latex used to be the go-to paint for just about everything, latex is not resistant against weather conditions and rust on most metals. When painting metal surfaces that are prone to rust, such as toys, mailboxes and siding, it is recommended that you use oil-based color paint.

Acrylic Latex Paint

Though latex paints are not suitable for most metals, they are fine for use on aluminum surfaces. This is because they leave a smooth finish; they are especially found on aluminum siding of homes and recreational vehicles. When using acrylic latex paint, wash the surface and dry it thoroughly before applying the paint. The paint needs to be 100 percent acrylic latex paint with no additives.

Metallic Paints

Metallic paints can have a different finish when applied to metal surfaces. You can get metallic paints in spray paint form or in oil-based paint cans. Prior to applying metallic paints, sand the surface of any previous rust and imperfections. Remove flakes of old paint on the metal surface so that the imperfections don't show when the paint surface hits the light.