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The study aims to compare tribological properties between laser dimple textured surface and drilled dimple textured surface, and to analyze the influence of dimple hardened edges and ability of trapping wear debris on wear properties of dimple textured surfaces.

Circular textured dimples were produced on AISI 1,045 specimen surfaces using laser surface texturing (LST) and drilled surface texturing (DST) methods. Tribological behaviors of LST, DST and non-textured specimens were studied using ball-on-disc tribo-tester. Metallographic structures, dimples and worn surface morphologies were observed using a three-dimensional digital microscope. Hardnesses of substrate and dimple edges were measured.

There was no obvious difference in wear and friction coefficients between LST and DST specimens. Hardnesses of laser dimple edges were much higher than that of drilled dimple edges and specimen substrate. The hardened materials of laser dimple edge included recast zone and heat affect zone. Laser dimple was cone-shaped and drilled dimple was cylinder-shaped. Drilled dimple had a better ability of trapping wear debris than laser dimple. Non-uniform wear phenomenon occurred on worn surfaces of LST dimple specimens.

The ability of textured dimples to trap wear debris is affected by single dimple volume. Hardened edges of dimples cause non-uniform wear on worn surfaces of LST specimens.

The use of high quality or exotic materials such as heat resistant alloys, high strength steels, stainless and aluminium alloys provide many answers to designers requiring solutions to specific problems, especially in the aerospace industry. However, the downside is that they are often difficult and costly to machine and can pose tremendous problems to production engineers due to their machining characteristics. Machineability, swarf control, work‐hardening and surface finish are a few of the prime headaches facing the production people with drawn‐out cycle times, high tooling bills, low machine utilisation and constant attention geneate concern for management.

THE Rockwell hardness number is based on the additional depth to which the penetrator is driven by a heavy load beyond the depth to which the same penetrator has been driven by a definite light load. A minor load is applied and often, without moving the specimen, a major load is applied. The major load is then removed leaving the minor load on, and the hardness number is indicated on the dial.

THE USE OF copper‐coated steel strip in place of plain steel or non‐ferrous metals in a number of applications has led to the solving of certain fabrication problems, improved product quality and a reduction in the costs of a range of component parts.

AEROSPACE is a very broad field and in order to deal with sheet metal applications in a little detail it is proposed to limit this article to airframes where the largest usage of sheet metal occurs.

Outlines how Parker Hannifin used Sandvik duplex stainless steel to provide higher corrosion resistance for its tube fittings for the paper industry. Describes how ferrules were the weak link in the chain and how Parker Hannifin developed new materials.

The purpose of this paper is to illustrate how often survivors are dismissed and unsupported in response to actively reaching out for help with distress. The author hopes the vignettes written about in this piece will serve to support and contribute to a body of work, which will educate professionals how to better support. The author shares various experiences when opportunities to help were denied and the impact this had on recovery. It is also noted that the responses of some health professionals mirror the original trauma suffered and therefore add to distress unnecessarily.

The author has written about various experiences in different settings in which the support offered fell below professional standards and contributed to further unnecessary distress. The writing is evocative and rich in descriptive detail of the event and then implications of the event on recovery.

The author concludes that it is helpful to use experiences of being dismissed and unsupported by various professionals to contribute to a body of work, which will hopefully educate and support those in caring professions to support survivors better. The author notes that responses to requests for help can unintentionally and intentionally further exacerbate the distress already experienced by those living with traumatic early life experiences and relational abruptions.

This is the author’s unique and first-hand lived experience of reaching out for help in relation to the distress experienced as a result of early life traumatic and adversarial experiences. The author notes that it is helpful to write about these difficult experiences with the hope that they will inform educational programmes to support health professionals in how they respond to people experiencing trauma. This has helped the author regain a sense of agency in contributing to the prevention of further unhelpful responses from various health professionals to those in distress. The vignettes are rich, deeply evocative and moving. The writing process also helped the author make sense of these further difficulties and how they impacted the recovery process.

A Selection of Equipment of Use in the Production and Maintenance of Aircraft, Missiles, Space Vehicles and their Components. A new spark erosion machine, based on the ‘Bridgeport by Adcock & Shipley’ miller, is now in production. This machine is powered by the new Linderode ‘Saturn’ console and alternator, manufactured by Linderfort Ltd. of Bletchley. On maximum, it gives a metal removal rate of 2,300 cu. mm./min. on only 48 kVA, and can be controlled down through three rotary switches to give a surface finish of 10 micro‐inches.

Fig. 1 shows a small tool which has been produced by Civitas Trading Corporation Ltd., Wigmorc House, 10 Duke Street, London, Wl, forthcremoval of ball bearings from shafts without damaging the race. A range of collets are provided to fit various types of bearings, and these are held in a self‐centring chuck which causes them to grip the inner race. The hollow body of the tool carries a thrust pin which is made in two parts separated by a ball bearing, to prevent the surface of the end of the shaft being damaged by the turning of the pin end. The threaded thrust pin is screwed home with a tommy bar and the race drawn offthc end of the shaft. It is claimed that no damage is caused to the race, and it can be used again if not otherwise due for replacement. Extension tubes are available to cater for bearings mounted at a distance along the shaft beyond the reach of the tool. The device is known as the Tracta ball and roller bearing extractor, collets being also provided which will fit roller races.

The purpose of this paper is to develop an energy-efficient and dynamically improved thrust ball bearing using textured race. A texture has been used on the stationary race of the test bearing to conduct the long-duration experiment for exploring its tribological and vibrational behaviours under starved lubricating condition using micro size MoS2 blended grease. The performance behaviours of the textured race bearing have been compared with conventional bearing (i.e. having both races without textures) under the identical operating conditions for demonstrating the advantages of textured race.

Texture was created on stationary race of the test ball bearing (51308) using nano-second pulsed Nd: YAG laser. Performance parameters (frictional torque, temperature rise and vibrations) of textured ball bearings were measured under severe starved lubricating conditions for understanding the critical role of texture in the long duration of the test. S-type load cell and miniature accelerometer were used for measuring the frictional torque and vibration, respectively. Bulk temperature at stationary races (at the back side) of test bearings was measured in operating conditions using a non-contact infrared thermometer.

Significant reduction in frictional torque and decrease in amplitude of vibration with textured ball bearing were found even under the severe starved lubricating condition in comparison to conventional bearing.

There is dearth of research pertaining to the performance behaviours of ball bearings using textures on the races. Therefore, an attempt has been made in this study to explore the tribo-dynamic performance behaviours of a thrust ball bearing using a texture on its stationary race under severe starved lubricating condition for the longer duration of the test.