Ted R. Massa

Bio: Ted R. Massa is an academic researcher from Kennametal. The author has contributed to research in topics: Carbide & Cermet. The author has an hindex of 18, co-authored 43 publications receiving 1183 citations.

Composite cermet articles and method of making

Abstract: Methods for making, methods for using and articles comprising cermets, preferably cemented carbides and more preferably tungsten carbide, having at least two regions exhibiting at least one property that differs are discussed. Preferably, the cermets further exhibit uniform or controlled wear to impart a self-sharpening character to an article. The multiple-region cermets are particularly useful in wear applications. The cermets are manufactured by juxtaposing and densifying at least two powder blends having different properties (e.g., differential carbide grain size or differential carbide chemistry or differential binder content or differential binder chemistry or any combination of the preceding). Preferably, a first region of the cermet comprises a first ceramic component having a relatively coarse grain size and a prescribed binder content and a second region, juxtaposing or adjoining the first region, comprises a second ceramic component, preferably carbide(s), having a grain size less than the grain size of the first region, a second binder content greater than the binder content of the first region or both. These articles have an extended useful life relative to the useful life of monolithic cermets in such applications as, for example, wear. The multiple region cermets of the present invention may be used with articles comprising tools for materials manipulation or removal including, for example, mining, construction, agricultural, and metal removal applications.

Rotatable cutting bit assembly with cutting inserts

Abstract: A rotatable cutting bit for penetrating an earth formation wherein the rotatable cutting bit includes an elongate bit body having a forward end and a rearward end. The bit body further defines a peripheral surface. The bit body has a first cutting insert affixed thereto at the axially forward end thereof. The first cutting insert has a first leading cutting edge and a first side clearance cutting edge. The first cutting insert is attached to the bit body so that the first side clearance cutting edge radially extends past the peripheral surface of the bit body so as to engage the earth formation.

Method of making composite cermet articles

Abstract: Methods for making, methods for using and articles comprising cermets, preferably cemented carbides and more preferably tungsten carbide, having at least two regions exhibiting at least one property that differs are discussed. Preferably, the cermets further exhibit uniform or controlled wear to impart a self-sharpening character to an article. The multiple-region cermets are particularly useful in wear applications. The cermets are manufactured by juxtaposing and densifying at least two powder blends having different properties (e.g., differential carbide grain size or differential carbide chemistry or differential binder content or differential binder chemistry or any combination of the preceding). Preferably, a first region of the cermet comprises a first ceramic component having a relatively coarse grain size and a prescribed binder content and a second region, juxtaposing or adjoining the first region, comprises a second ceramic component, preferably carbide(s), having a grain size less than the grain size of the first region, a second binder content greater than the binder content of the first region or both. These articles have an extended useful life in such applications as, for example, wear. The multiple region cermets of the present invention may be used with articles comprising tools for materials manipulation or removal including, for example, mining, construction, agricultural, and metal removal applications.

Method of molding green bodies

Abstract: Methods for making, methods for using and articles including cermets, preferably cemented carbides and more preferably tungsten carbide, having at least two regions exhibiting at least one property that differs are discussed. Preferably, the cermets further exhibit a portion that is binder rich and which gradually or smoothly transitions to at least a second region. The multiple-region cermets are particularly useful in compressively loaded application wherein a tensile stress or fatigue limit might otherwise be excessive for monolithic articles. The cermets are manufactured by juxtaposing and densifying at least two powder blends having different properties (e.g., differential carbide grain size, differential carbide chemistry, differential binder content, differential binder chemistry, or any combination of the preceding). Preferably, a first region of the cermet includes a first ceramic component and a prescribed binder content and a second region, juxtaposing or adjoining the first region, of the cermet includes a second ceramic component and a second binder content less than the prescribed binder content. The multiple region cermets of the present invention may be used in materials processing technology including, for example, compression technology, extrusion, supercritical processing, chemical processing, materials processing, and ultrahigh pressure.

Interface Character Distributions in WC–Co Composites

Abstract: The geometric and crystallographic characteristics of interfaces in WC–Co composites with a range of grain sizes and carbide volume fractions have been comprehensively characterized. The carbide crystals are most frequently terminated by (0001) and ð10 10Þ surfaces. The average number of carbide vertices per grain and the basal-to-prismatic face area ratio of the WC–Co interfaces increase with the carbide volume fraction. The three most frequently occurring WC/WC grain boundaries are 901 twist boundaries about ½10 10� ,3 01 twist boundaries about [0001], and asymmetric 901 boundaries about ½ 2110� .T he boundary populations do not vary with grain size or carbide volume fraction, suggesting that they are determined by the grain boundary energy anisotropy.

Kirk-Othmer Encyclopedia of Chemical Technology数据库介绍及实例

Abstract: 介绍了Kirk—Othmer Encyclopedia of Chemical Technology（化工技术百科全书）（第五版）电子图书网络版数据库，并对该数据库使用方法和检索途径作出了说明，且结合实例简单地介绍了该数据库的检索方法。

Forming structures from CAD solid models

Abstract: Method and apparatus for embedding features and controlling material composition in a three-dimensional structure (130) are disclosed. The apparatus comprises a directed material deposition apparatus having a source (124) of a focused laser beam, a deposition head (11) being coordinated in a plurality of coordinate axes, a controlled atmosphere chamber (128), a control computer (129), a plurality of feedstock (126, 127), a design rendering a solid model including embedded features, and a positioning stage (16) with a substrate (19) disposed on it. Said deposition head (11) can be a multi-axis deposition head, with a volumetric powder feed unit, a rapid acting metering valve for powder feedstock control, a laser delivery system having an optical fiber with heat protection, a laser beam shutter dump assembly and a pluraltity of powder delivery nozzles comprising coaxial gas stream means for reduced powder dispersion. Material properties can be engineered by adjusting laser exposure, material deposition and material constants.

Earth-boring rotary drill bits and methods of manufacturing earth-boring rotary drill bits having particle-matrix composite bit bodies

Abstract: Methods of forming bit bodies for earth-boring bits include assembling green components, brown components, or fully sintered components, and sintering the assembled components. Other methods include isostatically pressing a powder to form a green body substantially composed of a particle-matrix composite material, and sintering the green body to provide a bit body having a desired final density. Methods of forming earth-boring bits include providing a bit body substantially formed of a particle-matrix composite material and attaching a shank to the body. The body is provided by pressing a powder to form a green body and sintering the green body. Earth-boring bits include a unitary structure substantially formed of a particle-matrix composite material. The unitary structure includes a first region configured to carry cutters and a second region that includes a threaded pin. Earth-boring bits include a shank attached directly to a body substantially formed of a particle-matrix composite material.

Self-tapping resorbable two-piece bone screw

Abstract: An orthopedic interference screw has a hard, self-threading front section and a bioabsorbable rear section. The two sections are conjoined and threaded such that the hard front section cuts threads into the bone and the softer rear section follows the threads into the bone. Preferably, the screw has an axial bore for matingly receiving a turning tool such as a hex wrench.