Bead blasting can be used to refine a surface finish and is often used post Shot Peen to decontaminate the surface but also to reduce the overall surface roughness. It can be used to reduce the effect of machining marks and help to blend the surface to a homogenised finish.
It is primarily a process using either a glass or ceramic bead, these are available in a range of sizes and can be chosen to provide a required surface finish and texture.
It can be used to reduce the level of machining marks in a component but also to refine the surface so that a more regular and even finish is achieved. This is particularly beneficial where a series of different manufacturing methods have been used to produce a component or product each leaving a different surface condition. Bead blasting can also be used to restore a previously tarnished or aged finish back to a fresh clean surface finish.
This is a great finish for architectural elements either as an individual part to help it stand out or as an overall themed look.
Whilst bead blasting can produce a fine finish, for a coarser finish shot peening can be employed.
Bead blasting can be combined with other processes to enhance the overall impact as can be seen on this project with Littlehampton Welding where the images for the London Palladium ‘Wall of Fame’ had a series of squares laser cut to define images and then the surface was bead blasted to create an even surface finish.
The effect of bead blasting helps to refine the surface and hence reducing stress raisers and produces a more homogenised surface. It can also be used after shot peening to decontaminate the surface and remove the presence of any unwanted contaminants. In all of these instances the process will impart a small amount of compressive residual stress which can therefore improve the performance of the part.
If a mould requires a textured finish then Bead Blasting can be employed to produce and even textured finish. Depending on the product being moulded this can produce a matt fine textured finished part or a satin surface finish. If after many impressions the mould has worn the process can be repeated to maintain the original textured finish.
At Sandwell we have considerable expertise in this field and can advise on the most suitable technique depending on mould complexity, material and finish required.
The process can be applied to any metal item and is particularly effective on aluminium and stainless steel. When combined with a light aluminium oxide grit blast it is possible to eliminate light machining marks from the finished component. By varying the operating parameters of the process it is also possible to give the appearance of an aluminium ‘casting’ to a non-cast item. The many variables that contribute to the end result, once decided with our customer, are recorded and controlled to ensure repeatability for large batches or repeat work.
Mould as Machined
Mould Post Texturing