The assessment of primary calibrator purity is critical for establishing traceability to the International System Units (SI). Recently, quantitative nuclear magnetic resonance (qNMR) has been used as a determination method reference material development, and many related measurement techniques have designed acquire accurate reliable results. This review introduces recent advances in these (incl...

In this article, a new WC- Al2O3 composite tool material is successfully fabricated by vacuum hot-pressed sintering process with high hardness and flexural strength as well fracture toughness, which solved the problem of mutual restriction between toughness existing WC-Co materials. By adding Al2O3, WC-based cemented carbide significantly improved, are also improved. The mode WC-Al2O3 composite...

igh-temperature corrosion/oxidation has been shown to be a major contributor to the wear of tungsten carbide when machining medium density fiberboard (MDF) (Stewart 1992). Consequently, a change in the properties of the tool material to resist wear from the adverse wood machining environment needs to be investigated. A deep cryogenic treatment shows promise as a tool material treatment for incr...

Reported incidences of tool use and tool making for three wild chimpanzee populations increase from Mahale (12 and 3 types of use and making, respectively), Gombe (16 and 3) to Taï (19 and 6). Sticks are commonly used and prepared at all three sites. However, Taï chimpanzees seem to perform more modifications on the material before using it. They are also the only chimpanzees seen to pound obje...

Piezoelectric bimorph actuation has been successfully used in numerous types of microdevices, most notably micropumps. However, even for the simple case of circular geometry, analytical treatments are severely limited. This study utilized the finite-element method to optimize the deflection of a circular bimorph consisting of a single piezoelectric actuator, bonding material and elastic plate o...

Wire electric discharge machine (WEDM) is spark erosion in unconventional machining technique to cut hard and the conductive material with a wire as an electrode. The blanking die material SKD 11 is a high carbon and high chromium tool steel with high hardness and high wearing resistance property. This tool steel has broad application in press tools and dies making industries. In this research ...

A new size-independent indicator of scientific journal prestige, the SJR2 indicator, is proposed. This indicator takes into account not only the prestige of the citing scientific journal but also its closeness to the cited journal using the cosine of the angle between the vectors of the two journals' cocitation profiles. To eliminate the size effect, the accumulated prestige is divided by the f...

This paper is a state-of-the-art review of the use of cryogenic cooling using liquefied gases in machining. The review is classified into two major categories namely, cryogenic processing and cryogenic machining. In cryogenic processing also known as cryo-processing the cutting tool material is subjected to cryogenic temperatures as a part of its heat treatment process. The majority of the repo...

An important skill engineering students need to learn is how to solve problems by running experiments and using the results to make a sound diagnosis of the problem. This paper describes a software tool called Indie, which includes an authoring tool and a contentindependent engine, for delivering web-based learn-by-doing environments where students can practice such skill in an authentic task. ...