JRSA Inspections Blog: Metal Forming

Deformation of metals provides a number of advantages, like high duplication accuracy results from most deformation process, In general, the properties of wrought metals are improved over their cast counterparts and Thin sections can be more economically and more successfully produced than by casting A disadvantage is deformation process increase the probability of discontinuity formation
Cast Iron would have the least ductility
Forged products invariably exhibit directional properties
The mill working process used most to form metals into thee-dimensional shapes is forging
Forgings is generally selected for high strength and controlled property directionality
NDT is often used on products intended for secondary operations to ensure that further operations are not performed on material that contains discontinuities that could cause rejection of the manufactured part
An NDT method best suited to locating discontinuities caused by inclusions rolled into steel plate is ultrasonic testing
Slabs, Blooms and billets are the shapes that ingot is rolled into prior to variety of second operations
Before cold-finishing operations can be done on hot-rolled materials, cleaning is often done by immersing that hot-rolled material in acid baths in a process called pickling
During the steelmaking process, a large number of discontinuities such as slag, porosity and shrinkage cavities exist in the top of the ingot. These discontinuities are removed by cropping up to one-third off the top of the ingot
Discontinuities with their original ingot can be reduced in severity by the closing and welding of voids and the breaking up and en elongation of inclusion by hot rolling
Cold rolling sheet steel usually begins with a material that has been previously hot rolled to dimensions close to the size of the finished product
Cold working usually follows hot working
machinability and fatigue resistance are improved in most metals that have been cold worked
the mill working process performed principally on flat products and bars that improves hardness, strength, surface finish and dimensional accuracy is cold rolling
most seamless tubing made without welds is processed by piercing
With flat products such as cold-tolled strip and sheet, ultrasonic and radiation gages may be used to provide an accurate measurement of thickness
Most steel pipe is produced by forming and welding
A process that requires the use of large, powerful equipment that forms ductile material into a wide variety of long-length uniform cross-sectional shapes best describes extrusion
Among other factors, the advantageous effects of recrystallization depend upon the temperature at which deformation takes place
in drawing and deep drawing, the final shape often can be competed in a series of draws, each successively deeper. Recrystallization performed draws might effectively reduce the number of draws required
Spinning can be used to form spherical deep-drawn shapes
Shearing not describe the bend, stretch and shape metal into three -dimensional shapes with significant plastic flow and deformation (bending, forming and drawing yes)
Most new developments in sheet-metal forming typically use nonconventional energy sources. a common feature of these process is the use of energy sources that release large amounts of energy in a very short time
Electric motor housing is nor an application for powdered metal products, ( chemical catalysis, filtering elements and bearing yes)
powder metallurgy provides two unique advantages in metals processing. One is the capability to produce shapes and objects to refractory metals that are extremely difficult or impractical to melt; the other is to produce metal shapes with controlled porosity
A major purpose of pressing the metal powders during powder metallurgy processing is to compact the powders into mechanical and atomic closeness
Powder metallurgy products cannot attain 100% of theoretical density
In powder metallurgy process, sintering is in most cases a fully solid-state process