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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.

Because of the unrealistic demand of computer resources in terms of memory and CPU times for the direct numerical simulation of practical peen forming processes, a two‐stage combined finite/discrete element and explicit/implicit solution strategy is proposed in this paper. The procedure involves, at the first stage, the identification of the residual stress/strain profile under particular peening conditions by employing the combined finite/discrete approach on a small scale sample problem, and then at the second stage, the application of this profile to the entire workpiece to obtain the final deformation and stress distribution using an implicit static analysis. The motivation behind the simulation strategy and the relevant computational and implementation issues are discussed. The numerical example demonstrates the ability of the proposed scheme to simulate a peen forming process.

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.

To review the most commonly used mechanical surface enhancement (MSE) techniques and their applications available in aerospace industry.

A brief description of each technique, as well as advantages and disadvantages over other techniques are given. The effects of those techniques on the surface characteristics and service properties of treated components are summarised. Finally, the applications of such techniques in the aerospace industry are presented with descriptive illustrations.

Provides a know‐how information and also comparison of techniques. Guides researchers and engineers to proper and appropriate use of each technique for relevant case or application.

The list of techniques can be extended to a wider range which may perhaps include specific and special purpose surface enhancement methods. The applications given in the paper are mainly industrial examples of such techniques which may reduce its usefulness in academia.

A very useful source of information and reference for companies and engineers working in repair and production technologies of aerospace components, and also a valuable guidance for researchers and academia or for those who are intending to make a research on surface enhancement technologies.

This paper introduces the most commonly used MSE techniques and their effects on the service properties of aerospace components, and provides a practical help and information for people in the industry and academia.

This paper aims to present a methodology, based on traditional approaches, to predict the fatigue life and non‐propagating cracks of shot peened components and the damaging effect of a scratch created over the treated surface.

The finite element method is used to determine the actual strain at surface and fracture mechanics parameters calculated from cracks at the surface. The model considers residual stress (in order to introduce the effect of shot peening) and the scratch geometry. The total fatigue life is obtained by adding initiation life, to early and long crack propagation life using appropriate criteria.

Numerical predictions were compared with previous experimental tests, showing that this method is quite reliable for predicting both fatigue life and non‐propagating cracks of shot peened components, including the effect of damage due to a scratch.

The proposed method provides good results and a clear understanding of the fatigue process, however it requires a considerable amount of both material and shot peening parameters.

The methodology presented in this paper allows the determination of fatigue life and the prediction of non‐propagating cracks for components, including the effects of shot peening and scratch damage. These results can be used to quantify the scratch damage limits of components improved by shot peening.

This paper provides a useful tool for prediction of the effects of shot peening and scratch damage on fatigue life, using traditional approaches.

IMPACT Finishers Ltd is a surface treatment sub‐contracting organisation with its Head Office at Slough. A sister‐company to Vacu‐Blast Ltd., it is also a subsidiary of BTR plc.

In anticorrosive painting of structural steel the preparation of the metallic surface prior to the application of the organic coating is an important, if not more so, as the selection of the paint system.

Air conditioning, canteens and washroom facilities all contribute to the productivity and reputation of an organisation. Increasingly, unfortunately, standards of hygiene in these areas fail to meet the levels required by law, either because of a lack of specialist cleaning equipment, poor staff supervision or lack of time to perform adequate cleaning and maintenance. Facilities deteriorate, with subsequent risk to human health.

The purpose of this paper is to estimate the acceptable defect size amax after needle peening (NP) and predict the fatigue limit improvement through the use of NP for an austenitic stainless steel welded joint containing an artificial semi-circular slit on a weld toe.

Residual stress and hardness distribution were measured. Microstructures around the weld toe were observed to clarify the cause for the change in hardness after NP. Finite element method analysis was used to analyze the change in the stress concentration following NP. Fracture mechanics was used to evaluate amax after NP. The fatigue limits before and after NP were predicted by determining amax for several levels of stress amplitude.

The tensile residual stress induced at the surface of the weld toe prior to NP changed to a compressive residual stress after NP. The residual stress near the surface layer after NP exceeded the yield stress prior to NP due to the increase in yield stress as a result of work hardening as well as the generation of a deformation-induced martensitic structure. The stress concentration was reduced due to the shape improvement caused by NP. The estimation value of amax after NP and the prediction results of fatigue limits were in good agreement with the fatigue test results.

The proposed method is useful in improving the reliability of welded joints used in large steel structures, transportation equipments and industrial machines.

From an engineering perspective, it is essential to estimate amax and the fatigue limit of welded joints with crack-like defects. However, it is unclear as to whether it is possible to predict amax and the effects of NP on the fatigue limit for stainless steel welded joints.

Discusses the use of a corporate Internet in a geographically‐spread consulting firm, James Martin & Co., to share ideas, vision, client information and results. Illustrates with examples. Applications include a quarterly Employee Attitude Survey and regular discussion forums. Proposes that a well‐designed corporate intranet is a highly effective method of making intangible vision and mission pledges more tangible.