A method of detecting a polishing endpoint includes storing a plurality of library spectra, measuring a sequence of spectra from the substrate in-situ during polishing, and for each measured spectrum of the sequence of spectra, finding a best matching library spectrum from the plurality of library spectra to generate a sequence of best matching library spectra. Each library spectrum has a stored associated value representing a degree of progress through a polishing process, and the stored associated value for the best matching library spectrum is determined for each best matching library spectrum to generate a sequence of values representing a progression of polishing of the substrate. The sequence of values is compared to a target value, and a polishing endpoint is triggered when the sequence of values reaches the target value.

A method of detecting a polishing endpoint includes storing a plurality of library spectra, measuring a sequence of spectra from the substrate in-situ during polishing, and for each measured spectrum of the sequence of spectra, finding a best matching library spectrum from the plurality of library spectra to generate a sequence of best matching library spectra. Each library spectrum has a stored associated value representing a degree of progress through a polishing process, and the stored associated value for the best matching library spectrum is determined for each best matching library spectrum to generate a sequence of values representing a progression of polishing of the substrate. The sequence of values is compared to a target value, and a polishing endpoint is triggered when the sequence of values reaches the target value.

Dynamic regulation of contact pressures in a blade sharpening system is provided. An example multiphase grinding wheel has a grinding face with one or more abrasive concentric rings for sharpening the cutting blade of the log saw machine, and one or more padded concentric rings consisting of fiber padding. Sharpening with the multiphase grinding wheel improves cut quality, increases blade life, removes glues and varnishes from the cutting blade, reduces blade deformation, and hones the edge of the cutting blade. A pneumatic tensioning system uses air bladders to apply dynamic cushioning and processor-controlled contact pressure between the grinding wheels and the cutting blade during sharpening. The fiber-padded grinding wheels and the air bladder tensioner provide improved sharpness of the cutting blade and longer life for the mechanical components.

Dynamic regulation of contact pressures in a blade sharpening system is provided. An example multiphase grinding wheel has a grinding face with one or more abrasive concentric rings for sharpening the cutting blade of the log saw machine, and one or more padded concentric rings consisting of fiber padding. Sharpening with the multiphase grinding wheel improves cut quality, increases blade life, removes glues and varnishes from the cutting blade, reduces blade deformation, and hones the edge of the cutting blade. A pneumatic tensioning system uses air bladders to apply dynamic cushioning and processor-controlled contact pressure between the grinding wheels and the cutting blade during sharpening. The fiber-padded grinding wheels and the air bladder tensioner provide improved sharpness of the cutting blade and longer life for the mechanical components.

An abrasive article can include a body including a plurality of portions including a first abrasive portion and a second abrasive portion. The first abrasive portion can include a vitreous bond material and abrasive particles contained within the bond material. The second abrasive particles can include an organic bond material and abrasive particles contained within the bond material. The body can have a burst speed of at least 65 m/s. In an embodiment, the abrasive article can include an interior portion coupled to the first and second abrasive portions. In another embodiment, the interior portion can optionally include abrasive particles or a filler material.

An abrasive article can include a body including a plurality of portions including a first abrasive portion and a second abrasive portion. The first abrasive portion can include a vitreous bond material and abrasive particles contained within the bond material. The second abrasive particles can include an organic bond material and abrasive particles contained within the bond material. The body can have a burst speed of at least 65 m/s. In an embodiment, the abrasive article can include an interior portion coupled to the first and second abrasive portions. In another embodiment, the interior portion can optionally include abrasive particles or a filler material.

The disclosed technology includes a cutting tool comprising segments arranged around a periphery of a cutting tool. Each segment, of the plurality of segments comprising a first portion comprising a first material having a first hardness, a second portion comprising a second material having a second hardness, the second hardness being less than the first hardness, and a transition region. The transition region can include at least part of the first material and at least part of the second material. The transition region can have an overall third hardness that is less than the first hardness and greater than the second hardness. A first segment and a second segment of the plurality of segments can be attached to the periphery of the cutting tool such that at least the first portion of the first segment is aligned in a cutting direction with the second portion of the second segment.

The disclosed technology includes an abrasive cutting tool having a plurality of segments arranged around a periphery of the cutting tool. The plurality of segments can include a first segment having a first portion having a first concentration of abrasive material, and a second portion having a second concentration of abrasive material. The second concentration can be less than the first concentration. The cutting tool can have a second segment having a third portion having a concentration of abrasive material that can be similar to the concentration of the first portion, and a fourth portion having a concentration of abrasive material that can be similar to the concentration of the second portion. The first portion and the second portion can be reciprocally arranged in relation to the third portion and the fourth portion around the periphery of the cutting tool.

The disclosed technology includes an abrasive cutting tool having a plurality of segments arranged around a periphery of the cutting tool. The plurality of segments can include a first segment having a first portion having a first concentration of abrasive material, and a second portion having a second concentration of abrasive material. The second concentration can be less than the first concentration. The cutting tool can have a second segment having a third portion having a concentration of abrasive material that can be similar to the concentration of the first portion, and a fourth portion having a concentration of abrasive material that can be similar to the concentration of the second portion. The first portion and the second portion can be reciprocally arranged in relation to the third portion and the fourth portion around the periphery of the cutting tool.

An abrasive article includes a first plurality of abrasive particles and a second plurality of abrasive particles. The first plurality of abrasive particles differ in at least one of a size, an average weight and a shape from the second plurality of abrasive particles. The first plurality of abrasive particles are spaced from the second plurality of abrasive particles by at least a minimum distance in the x-axis direction, and both the first plurality of abrasive particles and the second plurality of abrasive particles extend in similar paths to one another with respect to the y-axis.