Wisdom utilizes both traditional methods of wire manufacturing – rolling and drawing. In both processes, alloyed rod stock as large as .250″ diameter is reduced down to as small as .020″ diameter.Rolling is a process in which metal stock is passed through a set of mechanically driven rolls. The process is deemed hot rolling if the metal stock is above its re-crystallization temperature and cold rolling if it is below its re-crystallization temperature. During hot rolling, the metal stock remains in a ductile and workable state, allowing for a greater amount of alteration. Because of high temperatures during rolling, the cooling process typically involves surface oxidation.
Cold rolling increases the yield strength of the metal stock, producing a denser, more compact end product. Also, the hardness is increased and the surface finish is smoother compared to hot rolling. Because of the change in the crystalline structure of the metal, ductility is affected and the metal stock must be annealed (heated) every so often to allow for workability.
Drawing is a process in which wire is pulled through either a single drawing die or series of dies. As the wire passes through the die(s), two things occur: the diameter decreases while the length increases. The volume remains constant. Drawing is classified as a cold working process because the wire is typically drawn at room temperature. Lubrication is frequently used during this process to extend die life as well as to maintain the integrity of the surface finish of the wire. We, however, can implement lube-free techniques for an exceptionally cleaner wire.
The basic composition of metal cored wire is a tubular electrode comprised of an outer metal sheath with a core of powdered materials. The metal sheath can be cobalt, nickel, iron, or stainless steel-based. The sheath conducts the electrical current during the welding and thermal spray processes. Metal cored wire’s internal powder composition consists of both elemental and alloyed powders such as nickel, cobalt, chromium, tungsten, molybdenum, and manganese to name a few.During the manufacturing process, a metal strip enters a mill, forming the outer metallic sheath to house the powder core. Using a specialized feeding process, the powder is fed into the sheath in a precise manner. The wire is rolled into a tubular shape and then drawn to a final size, ranging from .045″ to .125″ diameter. Typical processes that use these wires include Submerged Arc Welding (SMAW), Gas Metal Arc Welding (GMAW), and Wire Arc Spray/Thermal Spray.
Some of the advantages of using metal cored wires are that there are higher deposition rates, great sidewall fusion, reduced slag, reduced fumes and special alloys can be manufactured for specific applications. The product can be provided on spools, coils, or drums ranging from 25 to 500 pounds.
Components with extremely high near-net-shape requirements and surface qualities are produced by the investment casting process. The high precision of investment cast parts can reduce or eliminate some machining operations. This process is commonly used for the production of large quantities of parts. The investment casting process uses wax patterns assembled in tree forms on a runner. The completed assembly is coated with a ceramic slurry, allowed to dry and then heated to melt out the wax leaving a ceramic mould into which the molten alloy is poured.
Advantages
There are many advantages to using the investment casting process. Designers like to specify investment castings because of the design flexibility it gives them and the close dimensional tolerances, which the process makes available. In addition, alloys which are often difficult or impossible to machine can be investment cast with a high degree of consistency and repeatability.
Cost Reduction
Substantial savings are a powerful inducement for any casting buyer to switch to investment castings from other manufacturing methods. This is particularly true where components are purchased from outside vendors since it is easy to compare their cost for a component using an investment casting as the raw material against the cost of the previous method. Reductions in cost of 50% or more are not unusual.
Design Flexibility
Almost any shape, simple or complex, can be investment cast. Complex assemblies can be cast as a unit. Holes, slots, bevels, serrations, thin sections, knife edges and other configurations can be produced in investment castings.
Close Dimensional Tolerances
Close dimensional tolerances of /- .005 inch per inch are possible with investment castings. Many parts can be used “as cast” with no additional machining due to superior control of dimensions, tolerances and surface texture compared to other casting methods.
The sand casting process is used typically for larger parts and for small quantities of parts. Sand casting is capable of making fairly complex shapes using relatively inexpensive wood patterns. Sand, containing a natural or synthetic binder, is packed around a wood pattern, the sand is then tamped down to provide the two-part mold with adequate strength. The pattern is then removed, leaving a negative form in the mold.
Cavities can be produced in the sand casting by inlaying one or more cores in the mold. The two halves of the mold are clamped together ready for casting.
Our sand and face coat systems have been optimized to give superior surfaces for corrosion resistant alloys.
A wide range of cobalt alloys, nickel alloys and stainless steel alloys can be poured in our modern Sand Foundry. All castings produced can be finished to print in our Machine Shop.
The steel or aluminum pattern and runner are mounted on a flat steel plate, which is heated to a temperature that will cure the sand/resin mixture. The shell is stripped off and clamped against a flat or similarly moulded shell to form the mould cavity for the molten alloy, thus reproducing the pattern. For hollow components separately moulded cores are placed between the two halves of the mould before closing.
Complex moulds with integrated cores can be produced by the resin shell moulding process, allowing the production of parts with complex geometries. The resin shell process features comparatively good near-net-shape accuracies and good surface quality. Resin coated zircon sand is poured on to a heated pattern plate; the resin is cured and one half of a mould is thus formed. Two halves of a mould are then bonded together, ready for casting.
Centrifugal casting is ideal for high quality cylindrical components. As the name implies, centrifugal force is employed to exert pressure on the molten metal as it is poured into a spinning mould resulting in a dense part with a fine uniform grain structure. The wall thickness of the part is determined by the amount of poured metal. The centrifugal force presses the molten metal against the inner wall of the mould, densifying the metal and thus reducing shrinkage porosity and gas related defects. The integrity and wear resistance of these structures make them exceptional where there is frictional wear. Centrifugal castings are supplied in a semi or finished machine condition. A variety of moulds are available for speedy pours and deliveries.
Our cobalt and nickel based materials are rolled into the form of plate, sheet and bar products. A fundamental feature of the forming process is the improvement in the properties of the wrought material, brought about by changes to the grain structure during plastic deformation and heat treatment. During the forming of alloy sheet and bar the orientation and size of the fibres are optimised and the material achieves higher strength than cast material of the same chemistry.
After forming, the sheet is cut into blanks of suitable sizes by, for example, water-jet cutting or laser cutting. These blanks are then processed into finished parts.
Our wrought products fabricating department is skilled at press forming, roll forming and shaping the cobalt based wrought materials into finished components.
Powder Metallurgy is a process for making parts from metal powder. A mixture of metal powder and a binder is pressed into a mould to form the shape of the finished part. This preform is then heated to a temperature just below the melting point of the alloy. During this sintering process the diffusion of metal atoms between the alloy particles produces strong bonds between the particles. The final product has the advantage of a very fine grain size. Powder Metallurgy produces fully dense pressed components and is very economic for high volume production of small simple shapes. This technology allows us to manufacture uniform microstructures, which are free of nonmetallic inclusions and defects. Powder Metallurgy components are proven to have outstanding wear resistance and mechanical properties and provide exceptional reliability needed for anything from aerospace bearings to industrial saw teeth.
Surface finish is typically 125 RMS, with dimensional control dependent on the part size and geometry. Components should weigh less than 0.5 lbs and have a maximum surface area of 2.5 in 2. A variety of shapes can also be extruded such as diamond, wedge, rectangular and circular sections up to 1″ diameter and up to 40″ long. These extrusions are excellent for hardfacing consumables, cutters and wear pads.
For extreme demands on bond strength and wear resistance we hardface your components with one of a range of welding processes. A high-strength metallurgical bond exists between the welded overlay and the component, ensuring that the coating does not flake off, even under high mechanical loading of the component.
We use various thermal spraying techniques to protect your components against all forms of wear, such as abrasion, erosion and corrosion. Thermal-sprayed coatings are characterized by a mechanical bonding with the substrate, which provides very good bond strength. This coating technology is very useful for temperature-sensitive base materials.
One of the major characteristics of the Wisdom range of alloys is the extended life as a result of their specially formulated metallurgical properties. Alloys are more difficult to machine and grind than steel, in many instances specialized machining tools, equipment, processing parameters, and experience are required.
We maintain its investment program in modern cutting technology, with over two hundred machines and hundreds of specialized machine tools, for your full range of machining needs.
Machining Capacity
- Machining process, using metal cutting:
- CNC Drilling
- CNC Milling
- CNC Turning
- Machining process, using Grinding/Abrading
- Cylindrical Grinding Operations
- Cylindrical Grinding
- Centreless Grinding
- CNC form Grinding
- Flat Grinding Operations
- Flat Grinding
- Oscillating flat Grinding
- CNC flat form Grinding
- Double face round table flat Grinding
- 5 and 6 axis grinding
- Spherical Grinding
- Honing
- Flat Lapping
- Diamond Superfinish
- Cylindrical Grinding Operations
- EDM – Machining
- Spark Erosion
- Wire Cutting
