This paper describes some computer simulations of the breakage induced in a two-dimensional particle bed by the descent of a single Ž large grinding ball. These are approximate experiments related to ball-milling that are tractable by the simulation technique i.e., involve . relatively few particles . As a result of the impact of the grinding ball, the particles in the bed are broken andror sca...

The present study aims to investigate the residual stresses and surface hardening in ground components caused by the coupled effect of thermo-plasticity and phase transformation. A feasible numerical method was developed to accommodate appropriately the phase transformation in a workpiece experiencing critical temperature variation during grinding. The change of material properties was modelled...

Impinging jets are known as a method of achieving high convective heat transfer coefficients. One potential application of impinging jet heat transfer is the air jet cooling of a grinding process. A grinding process generates heat that must be dissipated to avoid thermal damage. To date, this has been achieved using flood cooling with a traditional coolant such as an oil and water mixture; howe...

A pavement surface having its texture deflections mostly directed downwards is said to have a “negative texture” and is expected to result in positive tire/road noise and rolling resistance properties. Negative textures are typical of porous asphalt pavements, but another way to achieve this is to grind-off the top of the asperities of a rough-textured surface. This paper explores the applicati...

Silicon wafers are the primary semiconductor substrates used to fabricate Integrated Circuits (ICs). Recently, the industry is making a transition from 200 to 300 mm wafers. To attain very flat 300 mm silicon wafers, grinding has been used to flatten the wire-sawn wafers. However, it is challenging for grinding to remove the waviness induced in wire sawing. To enhance the waviness removal abili...

The specification for the total thickness variation (TTV) of the device layers on thick-film silicon on insulator (SOI) wafers tighten for future applications. Therefore, the bulk removal polishing process of current technology after grinding cannot meet the demands in terms of flatness. The currently required amount of material removal for polishing out the induced sub surface damage (SSD) of ...

The paper details the effects of depth of cut and vibration amplitude when ultrasonic assisted (US) creep feed grinding Inconel 718 with an open structured alumina based wheel. The workpiece was actuated at a constant frequency (~20.5kHz) via a block sonotrode attached to a 1kW piezoelectric transducer-generator system. A full factorial experimental array comprising 12 tests was conducted invol...

This study investigates and models the grinding process of single crystal sapphire. Five parameters: the wheel speed, the feed speed, the vertical feed, the ultrasonic assistance and the crystallographic direction were considered via a design of experiments (DoE) approach. The responses were multiple but can be divided in three groups: the process, the machine and the grinding quality. DoE resu...

Optimization of grinding process is a multiobjective optimization problem. However, it traditionally has been solved as a single objective problem. In this paper, general, useful and practical multidisciplinary optimization methods are discussed for optimal design of surface grinding processes. The methods allow designer to explicitly consider and control multiple design objectives as an integr...

Cellulose nanofibrils (CNF) were spun into filaments directly from suspension without the aid of solvents. The influence of starting material properties and drying temperature on the properties of filaments produced from three different CNF suspensions was studied. Refiner-produced CNF was ground using a microgrinder at grinding times of 50 and 100 minutes. Filament spinning was performed using...