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Failure mode and effects analysis (FMEA) is a preventive technique in reliability management field. The successful implementation of FMEA technique can avoid or reduce the probability of system failure and achieve good product quality. The FMEA technique had applied in vest scopes which include aerospace, automatic, electronic, mechanic and service industry. The marking process is one of the back ends testing process that is the final process in semiconductor process. The marking process failure can cause bad final product quality and return although is not a primary process. So, how to improve the quality of marking process is one of important production job for semiconductor testing factory. This research firstly implements FMEA technique in laser marking process improvement on semiconductor testing factory and finds out which subsystem has priority failure risk. Secondly, a CCD position solution for priority failure risk subsystem is provided and evaluated. According analysis result, FMEA and CCD position implementation solution for laser marking process improvement can increase yield rate and reduce production cost. Implementation method of this research can provide semiconductor testing factory for reference in laser marking process improvement.

Growing needs for identification of small items for tracking and traceability purposes have led to the development of encoding structures known as matrix codes, capable of containing machine‐readable data. Describes practical applications for two particular types of high‐density code, the Data Matrix code and the DMT code. The applications relate to needs within the electronics industry, the automotive industry, and the aerospace industry. Through these examples an approach is presented for selecting appropriate codes and marking methods for given applications. The two codes considered, although both high‐density structures, exhibit different features. These are examined as a basis for considering their suitability for the various applications. Later in the paper the codes are discussed, along with the methods of printing and/or realising them in direct‐marking form.

Describes the properties and uses of a new colour‐change chemical for laser‐printing of human and machine‐readable data.

Presents the characteristics and modes of application of the chemical, its advantages over the current techniques of inkjet printing and laser‐marking, and a number of applications which show its distinctive features.

This chemical gives faster throughput and better print clarity than existing laser scribing processes, and opens up new anti‐counterfeiting techniques.

Draws attention to an invention that will make an impact on factory date‐coding procedures.

To discuss the application of direct part marking identification (DPMI) using 2D matrix codes, the use of which is increasing in industries as diverse as automotive and medical instruments.Design/methodology/approach – The benefits of 2D codes are explained, emphasising that they have sufficient storage capacity to provide data for tracking a part during its manufacture and through the supply chain and allow traceability throughout its lifetime. It describes the operation of Cognex, one of the leading manufacturers of ID products and also the world's largest supplier of machine vision systems is Cognex. It explains that initially the electronics industry exploited Cognex' code reading technology and an application at a German board manufacturer is described. Another system, at a diesel engine injector manufacturer in France, has 42 Cognex systems reading 2D codes and guiding robots in assembly. Also described is a new range of Cognex hand‐held and fixed‐mount 1D and 2D code readers “loaded” with software that allows reading in difficult conditions and with degraded or partially obscured codes.Findings – The DPMI market has expanded into industries other than automotive, which has prompted Cognex to establish a new division of ID products.Originality/value – The paper emphasises the importance of 2D codes in product traceability and indicates how vision technology is being utilised to read these codes even under difficult conditions.

The purpose of this paper is to reveal the friction and wear performance of grooves textured cylindrical roller thrust bearings with different groove dimensions under starved lubrication.

The groove dimensions include: width of grooves (WOG, 50 µm, 100 µm and 150 µm), depth of grooves (DPOG, 7 µm, 11 µm and 15 µm) as well as groove deflection angle (GDA, 45°). A fiber laser marking system was used to prepare groove patterns on the raceways of shaft washers. The friction and wear properties of grooves textured bearings were researched through a vertical universal wear test rig using a customized roller bearing tribo-pair under starved lubrication. Static finite element analyses were conducted to reveal their surface stresses. Through the comprehensive comparison and analyses, the influence mechanism of grooves on the tribological behavior of cylindrical roller thrust bearings was proposed and discussed.

When grooves textured bearings run under starved lubrication, their average coefficients of friction (COFs) and wear losses are all significantly reduced and much lower than those of smooth group. The influence of DPOG on the COF curves is significant, while the influence of WOG on the COF curves is a little weak. The influence of groove dimensions on the surface stresses of grooves textured bearings is weak, whether the WOG or DPOG. In this work, when the WOG is 100 µm and the DPOG is 15 µm, its average COF and wear loss are both the lowest, 0.0066 and 0.61 mg, respectively. Compared with the data of smooth group, its friction coefficient is reduced by 75.3% and its mass loss is reduced by 95.8%, showing a significant improvement in this condition.

This work can provide a valuable reference for the raceway design and reliability optimization of rolling element bearings.