Material flow

About: Material flow is a research topic. Over the lifetime, 3050 publications have been published within this topic receiving 36844 citations. The topic is also known as: material stream.

Material Flow during Friction Stir Spot Welding

Abstract: Material flow during friction stir spot welding is investigated. An examination of dissimilar Al 5754/Al 6111 spot welds was conducted to allow visualisation of material flow based on their differing etching characteristics. In addition, Al 6061–T6 spot welds containing Al2O3 tracer particles were examined to highlight the movement of material in different joint regions. It has been confirmed that upper sheet material is moved downwards into the lower sheet when a layer of upper sheet material is pushed ahead at the tip of the rotating pin, when upper sheet material becomes trapped at the root of the pin thread, and when an adhering layer of upper sheet material forms at the pin periphery during spot welding using a smooth pin. Lower sheet material is displaced upwards and outwards in a spiral motion when the rotating pin forms the keyhole. Two distinct zones of material flow are produced during friction stir spot welding: an inner flow zone close to the pin periphery where upper sheet material mo...

Supply Chain Dynamics—The Change Engineering Challenge of the Mid 1990s

Abstract: Much has been written concerning the supply chain demand amplification problem, best described by the ‘law of industrial dynamics’. Broadly speaking, if a supply chain can find a way to fluctuate, it will.The paper defines supply chains and reviews their current state of development. By way of a simulation example, the importance of good, shared, information flow is highlighted, as are several other strategies that lie more within the control of individual businesses. Good supply chain operation requires adequate design, led by a product champion committed to systems change. Persuasive evidence to support the product champion is therefore offered. Examples include internally generated demand amplification caused by human schedulers; an industrial supply chain case history; supply chain redesign via simulation; and a review of a proposed effectiveness framework which offers the possibility of integrating both modelling and design phases.The methodologies that are described herein may be universally applied...

Material flow stress and failure in multiscale machining titanium alloy Ti-6Al-4V

Abstract: Titanium Ti-6Al-4V alloy is a typical difficult-to-machine material due to its unique physical and mechanical properties. The material properties of Ti-6Al-4V play an important role in process design and optimization. However, the dynamic mechanical behavior is poorly understood and accurate predictive models have yet to be developed. This work focuses on the dynamic mechanical behavior of machining Ti-6Al-4V beyond the range of strains, strain rates, and temperatures in conventional materials testing. The flow stress characteristics of strain hardening and thermal softening can be predicted by the Johnson–Cook model coupled with the adiabatic condition. The predicted flow stresses at small strains agree very well with those from the split Hopkinson pressure bar (SHPB) tests, while the predicted flow stresses at large strains also agree with the calculated flow stresses based on the cutting tests with a suitable depth of cut. Heat fraction and temperature parameter control the range of thermal softening and the decrease rate of flow stress. The material may exhibit super plasticity at a small depth of cut with a large radius of the cutting edge in micromachining. Strain rate is one important factor for material fracture close to the cutting edge. The failure strain increases linearly with the increase of homologous temperature, while it only increases slightly with the strain rate.