Showing papers on "Liquid paraffin published in 1992"

Optical trapping of a metal particle and a water droplet by a scanning laser beam

Abstract: Laser trapping of a metal particle in water or a water droplet in liquid paraffin, which cannot be attained by irradiation of a TEM00 mode focused laser beam, was experimentally confirmed based on a scanning laser trapping technique. Although a metal particle or a water droplet experiences repulsive radiation force from a laser beam (1064 nm, focused into a ∼1 μm spot), scanning of the laser beam circularly around the particle was successful to optically trap and tweezer the particle. Water and ethylene glycol droplets dispersed in liquid paraffin were also shown to be manipulated independently by scanning double laser‐beam trapping.

Topical fish oil in psoriasis--a controlled and blind study.

Abstract: Omega-3 polyunsaturated fatty acids compete with arachidonic acid as substrates for lipoperoxidases, which transform them into leukotrienes with low biological activity. As this process, in skin, may benefit psoriatic patients, a randomized controlled single blind-study was carried out on a sample of 25 patients. In the study fish oil (FO) was compared with liquid paraffin (LP); both were topically applied and administered daily for 6 h under an occlusive dressing over a 4-week period. Evaluations were performed weekly assessing erythema, scaling, plaque thickness (induration) and itching. The results showed statistically significant improvement in erythema and scaling for both treatments compared to basal values; significant differences between treatments were achieved in scaling but not in erythema. Compared to baseline, FO significantly improved plaque thickness while LP did not. After 4 weeks, FO proved to be significantly better than LP. All patients accepted the treatment despite its unpleasant smell. Irritation and a burning sensation were reported in the FO treated plaque of one patient. This adverse effect reverted after completing the treatment. These findings demonstrate that topical FO shows a better performance than LP under an occlusive dressing.

Stabilization of Water/Oil/Water Multiple Emulsion with Hypertonic Inner Aqueous Phase

Abstract: Water/oil/water emulsion (w/o/w emulsion) was prepared with liquid paraffin, a hydrophobic surfactant (Span 80) and a hydrophilic surfactant (Tween 20) by a two-step emulsification procedure. The percentage of solute entrapped in the inner aqueous phase and the viscosity of the emulsion system increased with an increase in the concentration of solute (glucose of sodium chloride) initially added to the inner phase of the emulsion. The oil membrane of the w/o/w emulsion, which entrapped the hypertonic inner aqueous phase, was thick, and the release of the solute from the emulsion was slow. The viscosity of w/o/w emulsion entrapping a hypertonic inner aqueous phase was large, and consequently, separation of the aqueous phase was delayed. A decrease in the encapsulation efficiency of w/o/w emulsion during storage was considered to be the result of a rupture of the oil membrane. Destruction of the w/o/w emulsion followed first-order kinetics. The rate constant of destruction of w/o/w emulsion at room temperature could be predicted by meauring the destruction rate at a higher storage temperature.

Process for producing pasty paraffin

Abstract: An apparatus and a method for producing pasty paraffin from liquid paraffin comprises the use of an agitator for mixing the paraffin during its solidification within a receptacle. The viscosity of the paraffin is controlled by the monitoring of the power of a motor driving the agitator. Also, an apparatus is provided for producing candles in bottles from the pasty paraffin produced hereinabove. The apparatus comprises a filling head which receives the pasty paraffin and a continuous wick. A device is included for positioning a ferrule on the wick with the filling head being adapted for lowering into the bottle for positioning the ferrule at the bottom thereof and being also adapted to inject pasty paraffin in the bottle for setting the ferrule. The filling head is then retracted slowly from the bottle while injecting further paraffin therein for filling to a selected level the bottle. While the filling head retracts from the bottle, the continuous wick is made to extend from the bottom of the bottle centrally and longitudinally therein and, once the filling head is fully retracted from the bottle, the continuous wick is cut near or at the top of the bottle, thereby producing a candle in a bottle.

Steric repulsion of polyoxyethylene groups for emulsion stability

Abstract: Rapid coalescence was studied on liquid paraffin emulsion stabilized with a series of poly(oxyethylene) dodecyl ethers [C12H25 (EO),n=1, 2, 3, 4, 5, 6, 7, 8] and of poly(oxyethylene) nonylphenyl ethers [C9H19Ф(EO) n ,n=2, 4, 5, 6, 12] The turbidity of emulsion was measured as a function of the solution pHs at constant ionic strength of 01 mol dm−3 As a result, it was found that the emulsions (which were formed with C12H25(EO) n surfactants having less than four oxyethylene groups, or with C9H19 Ф(EO) n surfactants having less than six oxyethylene groups) brought about rapid coalescence in the bulk pH between 20∼35, which corresponded to the zero point of charges for the emulsions of the present systems According to the Tadros treatment for emulsion flocculation, the total flocculation potennual was estimated as a function of the distance relative to the number of oxyethelene groups in the surfactants The critical coalescence energy was obtained as −343 ×10−19 J for the C12H25(EO) n surfactants and −214×10−19) J for the C9H19 Ф(EO) n surfactants Furthermore, the formation of a hole for coalescence was estimated under the simple assumption that the coalescence was caused only by the energy dissipation

Pharmaceutical Emulsions and Creams

Abstract: O/W-creams with crystalline gel structures in general are four phase systems consisting of a hydrophilic gel phase and a lipophilic gel phase. The first one is able depending on the polarity of surfactants to incorporate a certain amount of water in between the lamellae and to further fix the bulk water (third phase) as coherent (outer) phase. The lipophilic gel phase stabilizes the dispersed (inner) phase (fourth phase). This concept showed its validity for gel structures in O/W-creams built up by ionic and non-ionic surfactants.

Composition for cleansing

Abstract: PURPOSE:To obtain a composition for cleansing, good in extensibility and having good permeability without thickening even if water is mixed therein by using a hydrophilic nonionic surfactant, an amphoteric surfactant, a water-soluble compound having hydroxyl group, a liquid oil and water together. CONSTITUTION:The composition for cleansing is obtained by using a hydrophilic nonionic surfactant (e.g. a polyoxyethylene alkyl ether), an amphoteric surfactant (e.g. lauryldimethylamine oxide), a water-soluble compound having hydroxyl group (e.g. glycerol or ethanol), a liquid oil (e.g. liquid paraffin or olive oil) and water together. This composition is in a readily handleable gelatinous or liquid form and excellent in feeling of use such as extensibility and slipperiness in application to the skin and good in permeability to fine parts of the skin. This composition is capable of performing the massaging while maintaining smooth touch during the application without thickening even by mixing of water. The composition is converted into ultra-fine oil-in-water type emulsified particles by further addition of water and can readily be removed together with fouling of makeup., etc.

Water-absorptive resin composition

Abstract: PURPOSE:To provide the water-absorptive resin composition useful for waterproofing sealing, etc., for tunnel, etc., having excellent flexibility, productivity and workability by a specific olefinic thermoplastic elastomer with a water- absorptive resin, a softener and a plasticizer in a specified ratio. CONSTITUTION:(A) 100 pts.wt. olefinic thermoplastic elastomer comprising 15-45wt.% PE-based polymer and 85-55wt.% ethylene-propylene-diene copolymer is blended with (B) 5-95 pts.wt. water-absorptive resin such as polyacrylate-based resin, (C) 2-50 pts.wt. softener such as liquid paraffin and (D) 2-50 pts.wt. plasticizer such as di(2-ethylhexyl) phthalate to give the objective composition.

Silicone putty compositions

Abstract: A silicone putty composition having high impact resilience immediately after preparation and providing a soft silicone putty having low plasticity is obtained by blending (1) a diorganosiloxane of the formula: R.sub.n SiO.sub.(4-n)/2 wherein R is a substituted or unsubstituted monovalent hydrocarbon group and n is a number of from 1.98 to 2.02, (2) an organopolysiloxane having a terminal alkoxy group, (3) boric acid or boron oxide, and (4) liquid paraffin. The composition is suited for use in toys and dampers.

Multiple-use thermal image transfer recording method

Abstract: A multiple-use thermal image transfer recording method includes the step of transferring a thermal image transfer ink component a plurality of times to an image-receiving medium from at least an identical portion of a thermal image transfer recording medium composed of a support and a thermal image transfer ink layer formed thereon, with the application of heat thereto. The thermal image transfer ink layer is composed of the thermal image transfer ink component mainly containing a coloring agent and a thermofusible material, and a porous resin component which is not thermally transferable, with both components having mutual releasability. The image-receiving medium has a recording surface, with the product of the absorption coefficient (Ka) of the recording surface measured by the Bristow Method (J. TAPPI. No. 51 - 87) at a pressure of 0.1 MPa, using an extra pure liquid paraffin, and the gradient (fc) of a linear portion of a load curve measured by a three-dimensional surface roughness analysis, being in the range of 2.0 to 6.0.

Sodium dichlofenac-containing percutaneous absorption type antiinflammatory-analgesic patch

Abstract: PURPOSE:To obtain the title patch by blending sodium dichlofenac as an active ingredient with a water retaining base such as sodium polyacrylate, a paraffin as a wetting agent, a release promoter, a stabilizer and menthol as a percutaneous absorption promoter. CONSTITUTION:The title patch comprising 0.1-5wt.% sodium dichlofenac as an active ingredient, sodium polyacrylate and sodium carboxymethyl cellulose as a water retaining base in a ratio of 1:(0.5-2), a paraffin, a liquid paraffin, a light liquid paraffin as a wetting agent, a release promoter and a stabilizer, water, and a combination of a purified oil such as l-menthol or pepper mint oil as a percutaneous absorption promoter with a nonionic surfactant. By making the patch, heavy side effects of oral agent and suppository are reduced and secure antiinflammatory and analgesic effects can be applied to inflammatory sites.

Functional morphology of Gene's organ in Haemaphysalis longicornis (Acari : Ixodidae)

Abstract: The structure and function of Gene's organ, which secretes the egg wax, were investigated inHaemaphysalis longicornis. The hatching rates of eggs deposited before and after the prevention of the eversion of Gene's organ were compared at the conditions of 30°C, 100% RH and soaking in liquid paraffin. The movement of Gene's organ was observed, and the structures of this organ in unfed and ovipositing females were examined with both light and scanning electron microscopes.

Utility of mixture of commercially available polymers as constituents of sustained-release microcapsules containing cefadroxil or theophylline.

Abstract: Hydroxy propyl methyl cellulose acetate succinate high grade (AS-HG) and ethyl cellulose (EC) mixture microcapsules containing cefadroxil or theophylline were prepared by a solvent evaporation method in liquid paraffin dissolved sorbitan tri-stearate as a dispersing agent, and their sustained-release properties were evaluated. The microcapsules prepared with AS-HG:EC (in a 2:5 weight ratio) mixture containing 20% of cefadroxil or theophylline exhibited apparent zero-order releasing pattern in pH 6 to 8, at 50 rpm and 37 degrees C (paddle method). These microcapsules were administered orally to beagle dogs and the plasma concentrations of cefadroxil or theophylline were measured periodically. As a result of in vivo investigation, a satisfactory sustained-release plasma pattern and an apparent zero-order process in the gastrointestinal absorption were confirmed by deconvolution analysis of both drugs.

Transparent cosmetic for skin

Abstract: PURPOSE:To obtain a transparent cosmetic for skin, excellent in transparency, touch and preservability in storage thereof in spite of containing a large amount of fluid oily components and low in irritation to the skin by blending an ether carboxylic acid-type anion surfactant with a fluid oily substance, a polyvalent alcohol and water. CONSTITUTION:With 0.05-3wt.% ether carboxylic acid-type anion surfactant of the formula (R is 10-20C alkyl; X is alkali metal or triethanolamine; (l) is 0 or 1; (m) and (m') are 0-16; (n) and (n') are 2 or 3; m+m' >=2), 40-90wt.% conventional oily substance (e.g. liquid paraffin) for cosmetic use, showing a liquid state at ordinary temperatures, 5-50wt.% polyvalent alcohol (e.g. glycerol) and 0.5-30wt.% water are blended. A perfume, a pigment, a preservative, a metal ion blocking agent, a skin-nutritive substance, etc., are added thereto as necessary, thus obtaining the objective cosmetic. The resultant cosmetic can be used as a gel-state or viscous transparent nourishing oil or cream, a transparent cream for massage, etc.

Induction of tumour necrosis factor alpha in experimental animals treated with hepatotoxicants.

Abstract: Administrations of hepatotoxicants namely carbon tetrachloride (CCl4:0.4 ml in 1.2 ml of liquid paraffin) and ANIT (1 ml of 1.5% solution in liquid paraffin) in Charles foster rats (force fed) and D-galactosamine (8 mg in water per swiss albino mouse, ip) induce the release of TNF-alpha in case of CCl4 and D-galactosamine. High TNF-alpha level was observed up to 48 hr in CCl4 and up to 24 hr in D-galactosamine treated animals. Elevated levels of biochemical like ALP and SGPT are also recorded. TNF-alpha level can be measured of tissue damage and prognosis in case of hepatitis.

W/o-type make-up cosmetic

Abstract: PURPOSE:To provide the subject cosmetic by mixing and dispersing water into water-repellent powder to obtain a structure containing fine water-droplets dispersed in the powder and adding an oil to the dispersion to get excellent applicability and cool and refreshing feeling. CONSTITUTION:A powdery material (e.g. yellow iron oxide and fine powder of titanium oxide) is coated with a water-repellent agent (e.g. methylhydrogen polysiloxane) using an air-flow dryer or spray dryer and the coated powdery material is heat-treated to obtain water-repellent powder. The objective W/O- type make-up cosmetic can be prepared by compounding 93-40wt.% of the water- repellent powder with 5-40wt.% of water and 2-20wt.% of an oil (e.g. oleic acid, liquid paraffin or squalane). The water-repellent powder is preferably coated with an oil containing Si-H group such as silicone oil and methylsilicone oil. The cosmetic has excellent applicability (spreadability, adhesivity, refreshing feeling and durability) and suitable as a foundation for summer season.

Reversed phase thin layer chromatographic methods for separation of cytokinins

Abstract: Silica gel layers were impregnated with a range of hydrophobic products. Only two such materials, liquid paraffin and the silicone fluid dimethylpolysiloxane, yielded thin layers which separated cytokinins effectively by reversed phase chromatography. The chromatographic behaviour of numerous cytokinins on these layers using a number of solvents is reported. The use of the layers and of integrated normal phase-reversed phase thin layer chromatographic systems to separate cytokinins in crude extracts is discussed.

Multiphase Flows in Ironmaking and Steelmaking Processes

Abstract: Multiphase flows are very popular in ironmaking and steelmaking processes and are characterized as follows:(1) The temperature of fluids in metallurgical reactors is higher than about 1500°C, hence measurements of transport phenomena (fluid motion, heat and mass transfer) are very difficult.(2) The flow in the reactors is highly turbulent (turbulence components are usually larger than mean flow values) and chemical reactions take place at the same time. Many “cold model” experiments have been carried out due to the difficulty in doing measurements under realistic conditions. Water, oil (silicone oil, pentane, liquid paraffin, etc.) and metals with low melting temperatures (mercury, Wood's metal, etc.) are Used as working fluids. Transport phenomena encountered in ironmaking and steelmaking processes (hot metal pretreatment, converter, second refining processes, etc.) are covered here and previous experimental and theoretical results on this subject are reviewed

Manufacture of negative electrode of nonaqueous electrolyte battery

Abstract: PURPOSE: To manufacture the negative electrode without adhering lithium to the pressurizing surface of a pressurizing die at the time of manufacturing the negative electrode of a nonaqueous electrolyte battery by pressing a rectangular piece of lithium metal with a die having the specified pressurizing surface. CONSTITUTION: A rectangular piece of lithium metal or lithium alloy is inserted into a negative electrode can or a lower die having the circular inner bottom surface. This rectangular piece is pressed by a die having the pressurizing surface, in which at least a part is formed into the rough surface, and having the material film having the excellent sliding property in relation to the lithium metal or lithium alloy in the rough surface of the pressurizing surface, and the rectangular piece is pressurized for deformation. In the case where the abutment area of the die is assumed at 100, the area of the rough surface at 65 or more is necessary. Shape of the die is formed into the concentric circular shape, spiral shape, radial shape, or random pattern having a groove at 0.02-0.30mm of depth. As the material film having the excellent sliding property, for example, the film made of liquid paraffin, fluoride group surface active agent, or Lewis base type organic solvent is used.

Water-absorbent resin composition

Abstract: PURPOSE: To obtain a resin composition excellent in water absorbency, productivity, etc, by mixing a specified thermoplastic olefinic elastomer with a hydrogenated diene copolymer, a water-absorbent resin, cellulose, an inorganic filler, a softening agent and a plasticizer CONSTITUTION: 100 ptswt thermoplastic olefinic elastomer consisting of 15-55wt% polyethylene polymer and 85-45wt% ethylene/propylene/diene copolymer is mixed with 10-100 ptswt hydrogenated diene copolymer 100 ptswt of this mixture is then mixed with 5-95 ptswt water-absorbent resin (eg a graft starch/acrylic acid salt polymer), 1-30 ptswt cellulose (eg wood pulp), 1-25 ptswt inorganic filler (eg calcium carbonate), 2-50 ptswt softening agent (eg liquid paraffin) and 2-50 ptswt plasticizer (eg dibutyl phthalate) to produce the objective composition COPYRIGHT: (C)1994,JPO&Japio

Pyrogenic aerosol composition

Abstract: PURPOSE:To obtain a pyrogenic aerosol composition useful for producing aerosol products of various uses, having proper exothermic action and warmth sensing action, comprising an oil, powder of zeolite, a surfactant and a propellant. CONSTITUTION:A pyrogenic aerosol composition comprising an oil, powder of zeolite, a surfactant and a propellant. To be concrete, safflower oil, glycerol, liquid paraffin, propylene glycol, etc., are used as the oil and, for example, coconut oil fatty acid polyoxyethylene (7) glycerol, diethylene glycol monoethyl ether, etc., may be cited as an oil for an aerosol composition for human body.

Participation of Macrogolstearate 400 lamellar phases in hydrophilic creams and vesicles.

Abstract: In binary Macrogolstearate 400 (MS 400)/water systems, lamellar surfactant arrangements can be detected by polarized light and transmission electron microscopy. As demonstrated by X-ray diffraction and differential scanning calorimetry, the alkyl chains of the emulsifier are in the crystalline state. Ternary systems with liquid paraffin represent optically isotropic, homogeneous o/w creams for a wide composition range. Incorporation of up to 50 mol% cholesterol into the MS 400 lamellar structures leads to a gel-liquid crystalline phase separation within the bilayer, thus enabling the formation of spherical nonionic vesicles. The transition enthalpy of the samples decreases linearly with increasing cholesterol concentrations. The Macrogolstearate 400/cholesterol vesicles proved to be stable in hydrophilic cream systems. Cationic vesicles can be prepared using cetyltrimethylammonium bromide (CTAB) as a charge inducer. Low-CTAB portions are inhomogeneously distributed within the bilayer, as detected by DSC. The results also indicate a perturbation of the alkyl chains packing for the positively charged vesicles.

Production of crosslinked and foamed material of water-absorbing resin

Abstract: PURPOSE:To obtain a foamed material having excellent mechanical properties, shape-retainability, durability and flexibility and useful for waterproofing seal, water-stopping agent, etc., by irradiating a specific resin composition such as a thermoplastic elastomer with ionizing radiation before or after the thermal foaming of the composition. CONSTITUTION:The objective foamed material is produced by compounding (A) 100 pts.wt. of an olefinic thermoplastic elastomer composed of 15-55wt.% of a PE polymer and 85-45wt.% of an ethylene-propylene-diene copolymer with (B) 5-95 pts.wt. of a water-absorbing resin such as polyacrylic acid salt resin, (C) 1-25 pts.wt. of an inorganic filler such as talc, (D) 2-20 pts.wt. of a softening agent such as liquid paraffin and (E) 1-10 pts.wt. of a foaming agent such as azodicarbonamide and irradiating the obtained resin composition with ionizing radiation (e.g. alpha-ray) before the thermal foaming of the composition or after the thermal foaming at a foaming ratio of <=8. The radiation dose is preferably 0.1-20 Mrad.

Image receiving sheet for use in thermal image transfer recording system

Abstract: An image receiving sheet for use in a thermal image transfer recording system, has an absorption coefficient (Ka) of 0.05 to 0.75 ml/m 2 ·(msec) 1/2 with respect to extra pure liquid paraffin at a pressure of 0.1 MPa when measured by the Bristow's Method (J.TAPPI No. 51-87). As such an image receiving sheet, an image receiving sheet having a recording surface with the product of (a) the absorption coefficient (Ka) with respect to the liquid paraffin (extra pure reagent) measured by the Bristow's Method (J.TAPPI No. 51-87) at a pressure of 0.1 MPa and (b) the gradient (fc) of a linear portion of a load curve obtained by a three-dimensional surface roughness analysis being in the range of 0.5 to 6.0 can be used. An image receiving sheet having a recording surface with the amount (V) of an ink transferred to the receiving sheet during 100 msec being in the range of 2.3 to 11.5 ml/m 2 can also be used. The amount (V) is obtained from (a) the absorption coefficient (Ka) and (b) the surface roughness index (Vr) of the recording surface, which are measured by the Bristow's Method (J.TAPPI No. 51-87) at a pressure of 0.1 MPa, with respect to the liquid paraffin (extra pure reagent).

Production of magnetic recording medium

Abstract: PURPOSE:To prevent sticking by subjecting a medium to heat treatment for a certain time at specified temp after calendering CONSTITUTION:A coating compsn containing a binder and magnetic powder is applied on a nonmagetic supporting body with a coater, and then the supporting body is subjected to calendering After calendering,the medium is subjected to heat treatment 100 - 140 degC for 20 - 90 seconds Moreover, higher fatty acid or its ester, fatty acid amide, liquid paraffin, silicone oil, etc, can be used as a lubricant alpha-alumina, Cr2O3, etc, can be used as an abrasive Thereby, sticking can be avoided and the curing time can be decreased

Solid oily cosmetic

Abstract: PURPOSE:To obtain an oily solid cosmetic having soft touch and high spreadability and giving excellent luster and durable make-up by compounding a specific amount of an oil-soluble resin to an oily solid cosmetic containing an oil, a wax and a powder CONSTITUTION:The objective oily solid cosmetic is produced by compounding 01-25wt% (preferably 20-20wt%) of an oil-soluble resin [eg ESCOREZ-1102,1202, etc, (aliphatic hydrocarbon produced by Tonex Inc) or ESCOREZ-1401 (an aliphatic/alicyclic hydrocarbon)] to an oily solid cosmetic containing an oil component such as liquid paraffin, squalane and olive oil, a wax such as polyethylene, solid paraffin, vaseline and candelilla wax and powder such as talc, mica, kaolin and titanium oxide The cosmetic is an epoch- making one satisfying various requirements for solid O/W-type emulsion cosmetic

Production of dialkyl zinc

Abstract: PURPOSE:To prevent the troubles caused by the by-production of black and tacky large solid particles in the synthesis of a dialkyl zinc by dropping and reacting a trialkyl aluminum to a suspension of zinc chloride CONSTITUTION:Trialkyl aluminum is slowly dropped to a liquid produced by suspending zinc chloride in a high-boiling hydrocarbon solvent such as liquid paraffin and is made to react at a low temperature (usually =1% (based on zinc chloride) of a metal hydroxide or metal oxide such as zinc hydroxide, alumina, celite or aluminum hydroxide to form the by-produced solid in the form of small particles having high dispersibility The dialkyl zinc can be produced on an industrial scale at a low cost without causing the inhibition of the reaction by the large-sized by-product

Acetate yarn for weft of high-speed air jet loom and its production

Abstract: PURPOSE:To obtain the title acetate yarn having reduced variability of number of projected parts between filaments constituting yarn and lessened variability of reaching of weft during weaving by a high-speed air jet loom by specifying the number of projected parts. CONSTITUTION:For example, the objective acetate yarn obtained by dry spinning using a spinneret having a spinning hole with hole shape of n-cornered (3<=n<=14) and comprising yarn having a projected part of (n-2) to (n+1) in the section of filament. The yarn is coated with 0.5-1.5% treating agent (based on weight of yarn) for weft comprising preferably 80-90 pts.wt. liquid paraffin, and wound in a cheese form.

Studies on Coal Slurry Fuel (Part 3)

Abstract: Model-COM was prepared. It consisted of graphite as a carbonaceous material, some inorganic materials (silica, alumina, kaoline, and montmorillonite) as ashes, and liquid paraffin as a liquid phase media. By using the Model-COM, its viscosity and cohesion behaviors (dynamic instability) were investigated with particular emphasis on the effects of those inorganic materials added. The viscosity of Model-COM was varied when kaoline and montmorillonite were added to it. The viscosity of the Model-COM increased with increasing amount of kaoline added, whereas its viscosity decreased gradually with increasing amount of montmorillonite added. The cohesion behavior of Model-COM was investigated by using "Flexible pipe passing test". In Model-COM the degree of cohesion was dependent on additive, temperature, and pipe shape, as was similar in the case of actual COM. The cohesion was increased in the order of materials added: alumina

Stress-corrosion cracking of 15cr-15ni-2.2mo titanium-modified austenitic stainless steels

Abstract: The stress- corrosion cracking (SCC) behavior of two alloys of titanium- modified austenitic stainless steels with different TiJC ratios in the 20% cold worked condition was studied in 45% boiling magnesium chloride (BP427 K) using the constant- extension rate testing (CERT) technique. The SCC susceptibility of the two titanium-modified alloys was assessed using the ratios of the values of ultimate tensile strength (UTS) and percent elongation in magnesium chloride and liquid paraffin, the susceptibility index (I), crack propagation rates (CPR), and stress ratios at different values of plastic strains. The results obtained on these alloys were compared with AISI type 316 stainless steel. It was observed that the two titaniummodified austenitic stainless steels had better SCC resistance than type 316 stainless steel, mainly due to their higher nickel content and, to a lesser extent, to the presence of titanium. Increasing the value of the TiJC ratio led to increased SCC resistance due to the availability of more free titanium in the solid solution. Fractography of the failed samples indicated failure by a combination of transgranular SCC and ductile fracture.