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Showing papers by "Cabot Corporation published in 1981"


Journal ArticleDOI
H. M. Tawancy1
TL;DR: In this paper, the long-term ageing characteristics of Ni-Mo-Cr alloys (the high-temperature HASTELLOY alloy S and the corrosion resistant hasselloy alloys C-4 and C-276) at 810 K were investigated.
Abstract: The long-term ageing characteristics of some commercial Ni-Mo-Cr alloys (the high-temperature HASTELLOY alloy S and the corrosion resistant HASTELLOY alloys C-4 and C-276) at 810 K were investigated. It was found that the three alloys undergo the following long-range ordering reaction: disordered f c c lattice → ordered orthorhombic, Pt2Mo-type superlattice. Ordering was found to cause considerable strengthening without severe loss of tensile elongation. Deformation in the ordered state occurred predominantly by twinning. The corrosion rates of alloys C-4 and C-276 in boiling sulphuric-ferric sulphate solution did not seem to be greatly affected by the long-range ordering reaction. In addition to ordering, the three alloys were also found to undergo grain boundary reactions. The resulting phase in alloys S and C-4 assumed a dispersed morphology and was identified as carbide, probably of the Type M12C. In alloy C-276, however, which contains higher amounts of iron and tungsten, the boundary precipitate was in the form of a continuous layer consisting of M12C and Mu-phase. This could account for the reduced tensile elongation of alloy C-276 relative to alloys S and C-4 and also to its high corrosion rate.

59 citations


Journal ArticleDOI
TL;DR: Martensitic, autstenitic, ferritic-austenitic, and high-nickel stainless steels were tested for their resistance to localized corrosive attack and to stress corrosion cracking in media containing chloride, saturated with CO2/H2S gas as mentioned in this paper.
Abstract: Martensitic, autstenitic, ferritic-austenitic, and high-nickel stainless steels and high-iron, nickel-base alloys are tested for their resistance to localized corrosive attack and to stress corrosion cracking in media containing chloride, saturated with CO2/H2S gas. Several testing environments are used in order to simulate service applications in deep H2S wells, deep CO2 wells, and enhanced recovery by CO2 injection. The alloys' performances are compared at different strength levels (0, 20, and 50% cold work), and the effects of temperature and CO2/H2S content are examined. The overall resistance of each class of alloys is outlined. Furthermore, within the same class of alloys, the differences are described with respect to localized corrosion and to stress corrosion cracking resistance.

12 citations




Patent
18 Sep 1981
TL;DR: In this paper, the use of certain heat-treated carbon blacks as stabilizers against the effects of degradation caused by visible and ultraviolet light in the preparation of polypropylene resin compositions containing conventional antioxidants which impart thermal stability to the polyethylene resin.
Abstract: This disclosure relates to the use of certain heat-treated carbon blacks as stabilizers against the effects of degradation caused by visible and ultraviolet light in the preparation of polypropylene resin compositions containing conventional antioxidants which impart thermal stability to the polypropylene resin.

8 citations


Book ChapterDOI
01 Jan 1981
TL;DR: In this paper, the flow of interdendritic liquid and macrosegregation in ingots prepared by electroslag remelting (ESR) were derived and compared with macrose segregation measured in experimental ingots.
Abstract: Equations for predicting flow of interdendritic liquid and macrosegregation in ingots prepared by electroslag remelting (ESR) are derived, and computer predictions of macrosegregation based on these equations are compared with macrosegregation measured in experimental ingots.

6 citations


Patent
20 Aug 1981
TL;DR: In this paper, an improved system for detecting the location of a molten metal/slag interface during the casting of electroslag remelted hollows is provided, which includes a gamma ray radiation source (30) and a scintillation counter (40).
Abstract: An improved system for detecting the location of a molten metal/slag interface during the casting of electroslag remelted hollows is provided. The system includes a gamma ray radiation source (30) and a scintillation counter (40). The source (30) and counter (40) reside outside the casting crucible (1) and are held in fixed spatial relationships with respect to one another and with respect to the mandrel (10). The radiation from the source (30) is directed through the crucible (1) and through the annular casting zone (9) defined between the sidewalls of the upwardly driven mandrel (10) and the crucible (1). The counter (40) provides an electrical signal responsive to the rate of radiation events detected thereby.

6 citations


Journal ArticleDOI
G. R. Cotten1
TL;DR: In this article, simple shear measurements can be done by means of a variety of laboratory instruments such as shearing disks, concentric cylinders, or capillary rheometers, which can be successfully used to predict the flow of fluids through tubes and some more complex processes, like extrusion and mixing.
Abstract: Simple shear is the customary mode of deformation for the study of rheology. Simple shear measurements can be done by means of a variety of laboratory instruments such as shearing disks, concentric cylinders, or capillary rheometers. The results so obtained have been successfully used to predict the flow of fluids through tubes and some more complex processes, like extrusion and certain aspects of mixing. However, simple shear experiments do not provide all the information necessary to describe processability of polymers. In particular they are totally unrelated to phenomena of extrusion shrinkage (die swell), extrusion appearance (melt fracture), or crumbling on the mill. A better understanding of these phenomena can be obtained by examining polymers in simple extensional flow.

3 citations


Patent
08 Jul 1981
TL;DR: In this paper, a composite article consisting of a pin and an enclosing member formed from a dissimilar material is described, which is used as a welding stud and a process for producing the article.
Abstract: A composite article having particular utility as a welding stud and a process for producing the article. The article is comprised of a pin and an enclosing member formed from a dissimilar material. The pin is comprised of a head and a shank. The pin is formed from a metal. The cross-section of the head is larger than that of the shank in a direction normal to the length of the pin. The enclosing member fits over and is adhered to the shank. The enclosing member is formed from material in powder form. It is placed upon the shank and sintered thereon. The enclosing member fits up against the head so that the article is substantially devoid of a gap therebetween. The absence of a gap is attributable to the shape of the shank. The cross-section of the shank is larger, in a direction normal to the length of the pin, adjacent the head than over other parts thereof.

2 citations




Patent
16 Oct 1981
TL;DR: In a previous work as discussed by the authors, we have presented the definition of a trait in the context of the OXYGENE project, which is a process for the preparation of a pipeline.
Abstract: L'INVENTION A TRAIT A UN PROCEDE POUR SEPARER DES METAUX REFRACTAIRES DE DECHETS D'ALLIAGES RESISTANT A L'OXYDATION. LES DECHETS SOUS UNE FORME FINEMENT DIVISEE SONT CALCINES 12 EN PRESENCE D'UN GAZ CONTENANT DE L'OXYGENE ET D'UN SEL DE METAL ALCALIN A 800-1150C PENDANT 0,25 A 4 H. CE TRAITEMENT TRANSFORME LES METAUX REFRACTAIRES EN MOLYBDATES, TUNGSTATES, CHROMATES, VANADATES, NIOBIATES ET TANTALATES ALCALINS ET LES METAUX DE BASE EN OXYDES. LE PRODUIT CALCINE PEUT ENSUITE ETRE LIXIVIE 14 PAR L'EAU EN DONNANT UNE LIQUEUR QUASI DEPOURVUE DE METAUX DE VASE ET RICHE EN METAUX REFRACTAIRES. LES METAUX REFRACTAIRES ET LES METAUX DE BASE PEUVENT ENSUITE ETRE RECUPERES PAR DES TECHNIQUES HYDROMETALLURGIQUES CLASSIQUES.

Patent
30 Oct 1981
TL;DR: In this article, the authors present a procedure for a pre-parter UN SUPERALLIAGE, PAR EXEMPLE, NICKEL-CARBONYLE, A LA POUDRE OBTENUE, A LIER PAR FRITTAGE LE MELANGE POUR FORMER UN "GATEAU", PUIS A TRAITER, PUIS a TRAITer CE MELANGER UNE PARTIE EGALE A CELLE RETENUE DE.
Abstract: L'INVENTION CONCERNE UN PROCEDE POUR AMELIORER LES CARACTERISTIQUES DE COMPRESSION D'UNE POUDRE DE METAL PRATIQUEMENT INCOMPRESSIBLE. CE PROCEDE CONSISTE A PREPARER UN SUPERALLIAGE, PAR EXEMPLE UN ALLIAGE A BASE DE NICKEL, DUQUEL UNE PARTIE D'AU MOINS UN METAL EST ENLEVEE, A ATOMISER L'ALLIAGE EN FUSION ET A LE BROYER EN POUDRE FINE, A MELANGER UNE PARTIE EGALE A CELLE RETENUE DE, PAR EXEMPLE, NICKEL-CARBONYLE, A LA POUDRE OBTENUE, A LIER PAR FRITTAGE LE MELANGE POUR FORMER UN "GATEAU", PUIS A TRAITER CE MELANGE POUR FORMER L'ARTICLE SOUHAITE. DOMAINE D'APPLICATION: METALLURGIE DES POUDRES.