Use of fine-grained pentaerythritol, dipentaerythritol or a mixture of these compounds as a pore forming additive in porous ceramic products such as ceramic abrasive wheels and ceramic filters.
A method of producing an abrasive roll comprises the steps of forming a mixture of substances such as abrasive grains, a bond, a temporary caking agent and a pore forming agent, molding the mixture into a body having a predetermined shape, and drying and then burning the body. The pore forming agent is constituted from a rice hull powder sieved to have a predetermined particle size, thereby enabling to produce an abrasive roll of high porosity which has pores having substantially ball-like shape and substantially uniform size and includes a bond having portions of high SiO.sub.2 concentration each adjacent to and surrounding one of the pores.
A method of producing an abrasive roll comprises the steps of forming a mixture of substances such as abrasive grains, a bond, a temporary caking agent and a pore forming agent, molding the mixture into a body having a predetermined shape, and drying and then burning the body. The pore forming agent is constituted from a rice hull powder sieved to have a predetermined particle size, thereby enabling to produce an abrasive roll of high porosity which has pores having substantially ball-like shape and substantially uniform size and includes a bond having portions of high SiO.sub.2 concentration each adjacent to and surrounding one of the pores.
A grinding tool, for attachment to a grinding tool carrier in a grinding machine, comprises a core member (3) which is provided with means such as a central bolt (5) for attachment to a tool carrier (6), and has at least two segments (21) of grinding material disposed circumferentially about and permanently fixed by an adhesive to the core member, grooves being defined between the segments of grinding material. The core member with segments of grinding material is easily replaced without replacing the tool carrier.
An abrasive article made from a plurality of abrasive composites bonded to form a three dimensional abrasive article. Each abrasive composite includes a plurality of primary abrasive particles bonded together by a first binder matrix to form a shaped or irregular abrasive composite. Present within the abrasive composite is an intra-composite porosity between and among the primary abrasive particles. Inter-composite porosity is present within the abrasive article between and among the abrasive composites. The abrasive article is used to grind glass and other workpiece surfaces to a mirror finish.
