Fluid structure interaction (FSI) modelling of deep hole twist drilling with internal cutting fluid supply

This paper presents a novel approach for coupling of thermal FE and CFD simulations to predict the temperature distribution in the cutting process. The developed FSI model considers experimentally validated workpiece temperature to simulate the heat convection interactions in drilling operations. This innovative method allows not only for the common analysis of the flow behaviour, but additionally for the detailed investigation of the temperature distribution within the cutting fluid. The simulation provides indications for an insufficient fluid supply of the cutting edge and the results can contribute significantly to the further optimisation of thermally high stressed cutting tools and processes.     

Cutting with coated tools: Coating technologies,characterization methods and performance optimization

Coated tools constitute the majority of the tools applied in material removal processes, rendering the employment of uncoated ones as an exception. A broad growing market of coated cutting tools has been developed. Moreover, numerous material- and manufacturing-engineers have joint their expertise, aiming at developing coatings meeting the needs for processing the most difficult-to-cut materials at the most extreme cutting conditions. The emerging of new workpiece, tool and film materials, the evolution of sophisticated coatings’ characterization methods and the continuous need for higher productivity rates, maintain vivid the industrial and scientific interest for further advancing this field.     

Deep hole drilling

Deep hole drilling processes, which differ significantly from conventional drilling processes, are relevant for a lot of different applications where holes with high length-to-diameter-ratios and very good qualities are necessary. This paper gives an overview of different methods, which are established to produce bore holes with demanding aspects related to diameter, length-to-diameter-ratio, bore hole quality, workpiece materials and complex internal contours. Beside the detailed explanation of the deep hole drilling methods and tools also the fundamentals of the deep hole drilling principle are explained and completely new developed figures and tables summarize the state of the art. In addition for the most important areas the latest results of process and tool development are included.     

Behaviour of uranium in hydroxyapatite-bearing permeable reactive barriers: investigation using 237U as a radioindicator

This study was undertaken to investigate the long-term performance of hydroxyapatite (HAP) as reactive material for the removal of uranium in passive groundwater remediation systems. 237U used as a radioindicator enabled tracking the movement of the contamination front through a test column without taking samples or dismantling the apparatus. The stoichiometric ratio between uranium and HAP was found to be 1:(487 +/- 19). Uranium removal by HAP is of pseudo first-order kinetics and the rate constant was measured to be (1.1 +/- 0.1) x 10(-3) s(-1). HAP can sorb more than 2900 mg/kg uranium. Possible reaction pathways of uranium and HAP are discussed. The data obtained enable the calculation of ideal lifetime for permeable reactive barriers (PRB) using HAP for uranium removal neglecting hydrological factors that may impair the function of PRBs.