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The purpose of this present work is to investigate how different parameters of the blast cleaning process affect properties and quality of brass parts surface. It aims to study the following process variables: particle abrasive shape: (spherical (S) and angular (G) shot), particle abrasive size (S170, G40 and G50) and the impact velocity (40 m/s, 60 m/s and 80 m/s).

An experimental approach based on three testing methods is used to quantify the analysis of particulate contaminants on substrates surfaces. These methods are: SEM, BSEM and EDXA plots from SEM imaging.

The results obtained clearly show that the particle embedment decreases with decreasing of the size of angular abrasive. An increase in the embedment could be noted as impact velocity increased. It was also found that the angular abrasives have delivered a contamination level higher than that delivered by spherical abrasives. Furthermore, it was demonstrated that the abrasive debris nature embedded in the treated surfaces is the iron. The coupling of this debris with the base metal (copper) in the presence of wetland causes an electrochemical corrosion. Then, if the contamination level decreases, the corrosion rate in treated brass parts by steel shots decreases also.

Search in the case of blast cleaning for the brass parts by steel shots has not been done previously. Using the spherical shape of the abrasive projected with a moderate impact velocity will be a solution in this case.

Introduction The post‐war period has seen great changes in the protective treatments applied to structural steel. Whilst corrosion scientists had urged for many years that removal of all rust, scale and surface contaminants before painting was essential to obtain full value from paint treatments, it was generally agreed until recently that to do so was impractical or ruinously expensive. Because the performance of the best available paints was not always adequate on poorly prepared steel, metallization treatments, designed to isolate steel by a complete cover of non‐ferrous metal, were sought, Galvanizing on pickled steel has been practised for many years on light gauge metal. For heavier sections metal‐spraying was developed, but to make this a viable process, mediods for cleaning the steel surface were essential. The grit‐blasting technique perfected for preparation for metal spraying began to be adopted as preparation for painting. However, progress was limited by gross variations in efficiency, and thus in costs, doubts about the type of surface desirable for paint and lack of definition of the bonus in performance to be expected from good preparation.

These directives were drawn up by a special study group and the Vereniging Metaalbeits at the request of the Netherlands Corrosion Centre. Last month the factors were listed determining the choice of preparation method and the specifications were given covering pickling by the sulphuric acid‐phosphoric acid method, and the hydrochloric acid (cold)‐phosphoric acid (hot) method. In this section, specifications are published covering the phosphoric acid‐phosphoric acid method, blast cleaning, scraping and wire brushing.

Blast cleaning is a production process that is often glossed over.

Service life or consumption rate of any reusable blast cleaning or shot peening abrasive is dependent upon its toughness and ability to withstand repeated impact. In cast steel abrasives, both structural and physical factors influence this. Isothermal, specifically austempering, heat treatment techniques are well established processes which can offer superior toughness and impact characteristics to both steels and irons. IsoShot is a new, bainitic, cast steel shot produced using an austempering technique.

A SPECIFICATION is essentially a method of ensuring that a purchaser obtains a product made and finished to his requirements. Any individual or group can prepare a specification but it must be technically feasible if it is to be accepted by the contractor. The preparation of a good specification is a skilled undertaking. It must cover all points that may give rise to disputes but it should not insist on a standard well above that actually required, as this will result in an unnecessarily expensive product. A specification may contain both aims and methods to be employed in achieving the aims, e.g. ‘ … remove all rust and scale by blast cleaning’. Clearly, the method specified must be capable of achieving the aim or disputes will inevitably arise. In the above phrase the substitution of ‘wire brushing’ for ‘blast cleaning’ would almost certainly lead to problems because generally all rust and scale cannot be removed by wire‐brushing. If the phrase were altered to ‘ … remove rust and scale by wire brushing’ this would be acceptable in that some rust and scale can be removed by wire brushing, but it is too vague for a specification.

Introduction Twenty‐five to thirty years ago in the U.K., it was an accepted fact that the first stage in the cleaning of steel destined for industrial fabrication, and prior to application of surface coatings was to allow it to weather in a stockyard.

New low‐cost mobile blaster. A new low‐cost mobile closed‐circuit blaster has been launched by Vacu‐Blast — the PB‐04U — a compact general‐purpose unit, ruggedly designed for a long reliable life.

The one‐step precision blasting method of glass bead cleaning, peening and corrosion removal involves impelling micron size spherical glass particles at controlled velocities against a work‐piece. The impact of the glass beads on the surface of the object pulverises and removes all forms of oxidation, corrosion and other foreign matter, including pit corrosion and corrosion in recessed and hidden areas around and under items such as rivets, The removal of all foreign matter down to the base metal is accomplished far more rapidly, hence far more economically, than currently utilised methods. There is no removal of base metal, no dimensional change and no contamination. Peening is achieved in a similar manner, as will be described later.