公开(公告)号：WO1988008413A1

公开(公告)日：1988-11-03

申请号：PCT/US1988001346

申请日：1988-04-21

Applicant: THE DOW CHEMICAL COMPANY

Inventor： THE DOW CHEMICAL COMPANY ,  PRUNIER, Arthur R., Jr.

IPC: C04B35/04

CPC classification number: C04B35/195

Abstract: Synthetic raw materials are used to prepare a sintered refractory body consisting essentially of cordierite having 47.5 to 56 weight percent SiO2, 31 to 40 weight percent Al2O3, 12 to 19 weight percent MgO, and 0.15 to 1 weight percent CaO, the body having a flexural strength of at least 138 MPa (20,000 psi). The cordierite body, with respect to impurities, has less than 0.3 weight percent total alkaline earth metal oxides other than MgO and CaO, less than 250 ppm Na2O, less than 150 ppm K2O and less than 500 ppm transition metals on the oxide basis. Thus, the cordierite of the invention has very low impurity levels yet good sinterability and, hence, high strength.

公开(公告)号：EP0650532A1

公开(公告)日：1995-05-03

申请号：EP93914193.0

申请日：1993-05-27

Applicant: THE DOW CHEMICAL COMPANY

Inventor： PYZIK, Aleksander J. ,  OTT, Jack J. ,  CARROLL, Daniel F. ,  PRUNIER, Arthur R., Jr.

IPC: C22C1 ,  C22C21 ,  C22C29

CPC classification number: C22C1/1036 ,  C22C29/062 ,  C22C29/14

Abstract: Subject boron carbide to a heat treatment at a temperature within a range of 1250 C to less than 1800 C prior to infiltration with a molten metal such as aluminum. This method allows control of kinetics of metal infiltration and chemical reactions, size of reaction products and connectivity of B4C grains and results in cermets having desired mechanical properties.

公开(公告)号：EP0650532B1

公开(公告)日：1997-03-05

申请号：EP93914193.3

申请日：1993-05-27

Applicant: THE DOW CHEMICAL COMPANY

Inventor： PYZIK, Aleksander J. ,  OTT, Jack J. ,  CARROLL, Daniel F. ,  PRUNIER, Arthur R., Jr.

IPC: C22C1/10 ,  C22C29/06

CPC classification number: C22C1/1036 ,  C22C29/062 ,  C22C29/14

Abstract: Subject boron carbide to a heat treatment at a temperature within a range of 1250 °C to less than 1800 °C prior to infiltration with a molten metal such as aluminum. This method allows control of kinetics of metal infiltration and chemical reactions, size of reaction products and connectivity of B4C grains and results in cermets having desired mechanical properties.

公开(公告)号：EP0370020A1

公开(公告)日：1990-05-30

申请号：EP88904320.0

申请日：1988-04-21

Applicant: THE DOW CHEMICAL COMPANY

Inventor： PRUNIER, Arthur R., Jr.

IPC: C04B35

CPC classification number: C04B35/195

Abstract: Des matières premières synthétiques sont utilisées pour préparer un corps réfractaire fritté se composant essentiellement de cordiérite contenant de 47,5 à 56 % en poids de SiO2, de 31 à 40 % en poids de Al2O3, de 12 à 19 % de MgO et de 0,15 à 1 % en poids de CaO, ledit corps présentant une résistance à la flexion d'au moins 138 Mpa (20000 psi). En ce qui concerne sa teneur en impuretés, le corps de cordierite contient au total moins de 0,3 % en poids d'oxydes de métaux alcalino-terreux, autres que MgO et CaO, moins de 250 ppm de Na2O, moins de 150 ppm de K2O et moins de 500 ppm de métaux de transition, chiffres calculés sur la base de la teneur en oxydes. Ainsi, la cordiérite de l'invention présente des niveaux d'impuretés très bas tout en ayant une bonne aptitude au frittage et, par conséquent, une grande résistance.