Effect of laminar air flow on probe burn for spring probe
This paper investigates transient heat transfer between a heated spring probe and its air environment. A continuum finite volume simulation is used to analyze of heat flow within and from the resistively heated probe to its environment. Experimental results are conducted for spring probe with laminar air flow and without air flow. The numerical results and experimental results are compared and very good agreement is observed.
Estimation of aluminum and gold bond wire fusing current and fusing time
Wirebonding is the common method for electrically connecting the semiconductor device to the external leads or pins. Permanent damage to wirebonds would occur if the wires could not dissipate the energy, due to excessive current, delivered through the wires. This current overstress damage is recognized as fused bond wires. In this paper, the simplified model developed by Loh (1983) has been used to predict the fusing time and the fusing current of aluminum and gold wires as functions of wire length and wire diameter. In addition, the equation obtained by Loh has been put into more convenient form by eliminating the dependence on the bond wire diameter. Results from both approaches have been presented in graphical form so that package design engineers would be able to estimate the fusing current for a given fusing time. Conversely, the fusing time for a given current passing through the wires could be easily obtained from the design graphs. >
Compressive and flexural properties of hemp fiber reinforced concrete
The compressive and flexural properties of hemp fiber reinforced concretes (FRC) were examined in this paper. Natural hemp fiber was mixed using dry and wet mixing methods to fabricate the FRC. Mechanical properties of the FRC were investigated. The main factors affecting compressive and flexural properties of the FRC materials were evaluated with an orthogonal test design. Fiber content by weight has the largest effect. The method for casting hemp FRC has been optimised. Under the optimum conditions, compressive strength increased by 4 %, flexural strength increased by 9 %, flexural toughness increased by 144 %, and flexural toughness index increased by 214 %.