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The purpose of this paper is to report the studies on the corrosion inhibition property of 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol (APTT) for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite.

The corrosion behavior of 6061 Al-15 vol. pct. SiC(p) composite was studied at different temperatures in 0.5-M sodium hydroxide (NaOH) solution in the presence of APTT by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopic techniques. The effect of inhibitor concentration and temperature on the inhibitor effect of APTT was studied. The surface morphology of the metal surface was investigated by scanning electron microscopy. The activation parameters for the corrosion of the composite and base alloy, as well as the thermodynamic parameters for the adsorption of APTT on the composite and alloy surfaces, were calculated.

The inhibition efficiency of APTT increases with the increase in the concentration of the inhibitor and decreases with the increase in temperature. The adsorption of APTT on the composite was found to be through physisorption, obeying Langmuir’s adsorption isotherm. APTT acts as a mixed inhibitor with predominant cathodic action on the composite.

APTT can be used as an inhibitor for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite in the NaOH medium.

This paper provides information regarding the corrosion inhibition property of APTT on 6061 Al-15 vol. pct. SiC(p) composite. An attempt was made to explain the mechanism of the inhibition action by APTT.

This research aims to describe the influence of weight per cent of graphite (Gr), applied load and sliding speed on the wear behavior of aluminum (Al) alloy A356 reinforced with silicon carbide (SiC) (10 Wt.%) and Gr (1 Wt.% and 5 Wt.%) particles. The objective is to analyze the effect of the aforementioned parameters on a specific wear rate.

These hybrid composites are obtained by means of the compo-casting process. Tribological analyses were conducted on block-on-disc tribometer at three different loads (10, 20 and 30 N) and three different sliding speeds (0.25, 0.5 and 1 m/s), at the sliding distance of 900 m, in dry sliding wear conditions. Optimization of the tribological behavior was conducted via the Taguchi method, and ANOVA was used for the analysis of the specific wear rate. Confirmation tests are used to foresee and check the experimental results. Examined samples were analyzed via a scanning electron microscope (SEM). Regression models for predicting specific wear rate were developed with Taguchi and ANN (artificial neural network) methods.

The biggest impact on value of specific wear rate has the load (43.006%), while the impact of Wt.% Gr (31.514%) was less. After comparison of the results, i.e. regression models, for predicting the specific wear rate, it was observed that ANN was more efficient than the Taguchi method. The specific wear rate of Al alloy A356 with SiC (10 Wt.%) and Gr (1 Wt.% and 5 Wt.%) decreases with a decrease in the load and weight per cent of Gr-reinforcing material, as well as with a decrease in sliding speed.

The results obtained in this paper using the Taguchi method and the ANN method are useful for improving and further investigating the wear behavior of the SiC- and Gr-reinforced Al alloy A356.

The increasing utilization of Al‐matrix composites in electronics packaging industry raises demands of solder materials with melting temperature at 400‐500°C. The purpose of this paper is to determine the thermal properties of two Ag‐Cu‐Sb alloys with the composition close to two eutectic points, and two Au‐Ag‐Ge alloys along the eutectic line, to observe the microstructures and to investigate the wettability of the alloys, and to evaluate the possibility for them to be used as medium temperature solders.

Four candidates of solder alloys in the Au‐Ag‐Ge (AAG1, AAG2) and Ag‐Cu‐Sb systems (ACS1, ACS2) were studied to reveal microstructures, melting points, wettabilities, and the interfaces between the solder and Al/SiC substrate coated with Au and Ni.

The paper finds that the ACS1 and ACS2 alloys possess small temperature gaps between solidus and liquidus: 422.9°C/429.2°C and 483.3°C/488.1°C, respectively. For two AAG alloys, the temperature ranges between solidus and liquidus are larger than 40°C. The wettability tests showed that two ACSs and AAG1 alloys have good wettability to the substrate. Similarly, except ACS2 alloy, the other alloys exhibit good adhesion with the substrate.

The paper shows that the ACS1 alloy and the AAG1 alloy could be used as the optimum solder materials for 400‐500°C owing to the good wettability and proper melting point.

In this paper, thermal analysis for a 1,200 A, 3.3 kV insulated gate bipolar transistor (IGBT) module was investigated and analysed using the three‐dimensional transmission line matrix (3D‐TLM) method. This paper also reviews the present status of the use of various thermal heat spreaders such as AlSiC MMC, Cu‐Mo and graphite‐Cu MMC and compares these with copper based heat spreaders and the use of aluminium nitride (AlN), diamond and BeO as substrates and their effect to dissipate the heat flux in heat sources localised in IGBT module design. The TLM method was found to be a versatile tool which is ideally suited to the modelling of many power electronic devices and which proved very useful in the study of transient thermal effects in a variety of device structures.

The purpose of this paper is to investigate the effect of SiC addition up to 60 percent SiC on the mechanical properties and thermal expansion of Al‐7vol.% Si/SiC composites.

Composite specimens containing 7, 15, 30, 45 and 60 vol.% SiC_p are fabricated by pressureless infiltration technique. The obtained metal‐matrix composites (MMCs) then are characterized for density, porosity, microhardness, ductility, and coefficients of thermal expansion (CTE).

The results show that the composite specimens have very low‐porosity volumes. Moreover, it is found that silicon carbide particles are distributed uniformly in the matrix. Both porosity and mean linear CTE of the composites decreases with silicon carbide volume fraction. However, higher amount of SiC_p reinforcement content tends to increase density, microhardness and improve ductility.

The processing employed in this paper would enable realization of electronic packages made out of Al‐Si/SiC_p MMCs.

This chapter focuses on visualization. Seeing the humanities differently is one of the amazing benefits of working with tools mentioned within this category. Whether it be more traditional visualizations like images or video or that which is considered a bit more advanced like augmented or virtual reality, the enhanced perspective gained through the use of these tools offers digital humanities scholars unprecedented disciplinary perspectives while helping to shape new research areas, questions, and understanding of humanity and culture. In addition to visualization and issues related to it, this chapter also examines gaming and how games and play are impacting the digital humanities in exciting ways.

The purpose of this paper is to evaluate the effect of solder wettability on the thermal performance of a thermo‐electric cooler (TEC) of a 980 nm pump laser module.

In this paper, TEC thermal performance has been evaluated using a heat pump test. The results were compared with scanning acoustic microscopy (C‐SAM) results in order to have a better understanding of the thermal behaviour of the TEC. In the C‐SAM experiments, images were taken at the interfaces between the housing and TEC, as well as at the interfaces between the chip‐on‐carrier (CoC) and TEC.

The heat pump test results indicate a strong correlation with the C‐SAM test results. The C‐SAM observations show good solder joint at the interface between the TEC and housing in the case of the device that yielded a good heat pump test result (11.5°C) and poor solder joints (gross de‐lamination) at the interface between the TEC and housing in the case of the device that yielded a poor heat pump test result (24.4°C). The C‐SAM observations did not show much difference at the interface between the CoC and TEC. The results from this study were used to qualify the post‐vacuum soldered laser pump devices at JDS Uniphase, Plymouth, UK.

The findings presented in this paper indicate that the level of solder wettability at the interfaces between the piece parts impacts the thermal performance of the TEC.