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Showing papers on "Tempering published in 1968"


Journal ArticleDOI
TL;DR: In this paper, the authors discussed the fracture of thermally tempered glass in terms of both the stored elastic strain energy in the glass due to tempering and the elastic energy release rate Of crack extension, 9.
Abstract: The fracture of thermally tempered glass is discussed in terms Of both the stored elastic strain energy in the glass due to tempering and the elastic energy release rate Of crack extension, 9. The latter is used to obtain an analytical correlation between the maximum tensile stress and the average particle size at time of fracture. The theoretical predictions are supported by experimental data obtained for various glass thicknesses and temper levels.

91 citations


Journal ArticleDOI
G.E. Pellissier1
TL;DR: In this article, the interrelationships among fine-scale microstructure, strength, and toughness have been investigated, including embrittlement phenomena, the effects of residual or impurity elements, and the micromechanisms of crack propagation.

58 citations


Journal ArticleDOI
TL;DR: In this article, the Mossbauer effect of 57 Fe in the iron-carbon martensite steels was measured during their tempering process, and the appearance of the e -, χ- and cementite phases and the bonding nature in them were studied.
Abstract: The Mossbauer effect of 57 Fe in the iron-carbon martensite steels was measured during their tempering process, and the appearance of the e -, χ- and cementite phases and the bonding nature in them were studied. It was clarified that the χ-carbide is formed at the tempering stage III a, the formation of which had not been fully proved in previous X-ray or magnetic measurements. It was also concluded that the electronic states of the iron atoms co-ordinating the carbon atoms in the martensite and the e -carbide formed in the stage I are substantially the same, suggesting that the motive force in the stage I is mainly the relaxation of the large strain energy in tne martensite structure. The observed localized and additive nature of the iron-carbon interaction, which was concluded from the linear relation between the amount of the internal field reduction and the number of carbon co-ordination for iron atoms in the various phases, seems to indicate that the Alexander-Anderson-Moriya's idea is applicable to ...

57 citations


Journal ArticleDOI
TL;DR: The sulfide cracking behavior of a number of carbon and low alloy steels is described in this paper, where it is shown that the susceptibility of a steels to sulfide crackability depends primarily on the microstructure of the steels.
Abstract: The sulfide cracking behavior of a number of carbon and low alloy steels is described Susceptibility to sulfide cracking is shown to depend primarily on microstructure Steels with uniform, spheroidized carbides in a ferrite matrix have the greatest cracking resistance at any given strength level The presence of untempered martensite in the microstructure drastically reduces cracking resistance Lamellar carbides resulting from either normalizing and tempering or isothermal transformation give rise to cracking resistance intermediate between steels fully quenched and tempered and steels containing untempered martensite

56 citations


Journal ArticleDOI
TL;DR: In this article, the magnetic behavior of the extracted precipitates is discussed, and the behavior of internal field, the TC and θD, as a function of the tempering temperature suggests a decrease of the relative carbon content with the increasing tempering temperatures.
Abstract: The precipitation of carbides in 0.7 wt%‐carbon steel as a function of tempering temperature has been studied through the Mossbauer effect, magnetic measurements, and x‐ray observations.The magnetic behavior of the extracted precipitates is discussed. The tiny clusters obtained by extraction after the early stages of tempering (up to 250°C) show the relation of these clusters to martensitic bct cells (``Johnson clusters'').The results obtained by further stages of tempering (250–500°C) show a decrease in the relative amount of the Johnson clusters, followed by a precipitation of ferromagnetic carbides. The behavior of the internal field, the TC and θD, as a function of the tempering temperature suggests a decrease of the relative carbon content with the increasing tempering temperatures. The Fe3C is formed toward 550°C.

41 citations


Patent
18 Apr 1968
TL;DR: A procedure for forming curved, tempered glass sheets by chemically tempering the sheets by means of a diffusion process and then bending the sheets to the desired curved form while the sheets are at a raised temperature which gives them a viscosity of no less the 10**10 poises is described in this article.
Abstract: A procedure for forming curved, tempered glass sheets by chemically tempering the sheets by means of a diffusion process and then bending the sheets to the desired curved form while the sheets are at a raised temperature which gives them a viscosity of no less the 10**10 poises, whereby the sheets can be bent after tempering without having to be subjected to extremely high temperatures.

30 citations


Patent
Aoki Koichi1, Inoue Tohru1, Mimura Hiroshi1, Sakurai Hiroshi1, Yano Seinosuke1 
18 Nov 1968
TL;DR: In this article, a heat-treating method of hot-rolled steel plate containing 1.5% to 10.0% Ni, 0.1% to 5.0%, and further at least one element selected from the group consisting of Mo, Cu, Cr, Nb and V, at need and the balance being substantially Fe, comprising subjecting one or more times repeatedly said hotrolled steelplate to heating to and sequent quenching from a temperature within the range between Ac1 and Ac3 points, then subjecting the steel plate to tempering treatment at
Abstract: Heat-treating method of hot-rolled steel plate containing 1.5% to 10.0% Ni, 0.1% to 5.0% Mn and further at least one element selected from the group consisting of Mo, Cu, Cr, Nb and V, at need and the balance being substantially Fe, comprising subjecting one or more times repeatedly said hot-rolled steel plate to heating to and sequent quenching from a temperature within the range between Ac1 and Ac3 points, then subjecting the steel plate to tempering treatment at a temperature below Ac1 point, thereby to improve largely toughness at low temperature and obtain excellent workability.

28 citations



Patent
29 Jul 1968

23 citations




Patent
23 Apr 1968
TL;DR: In this paper, a process and an apparatus for improving the properties of materials which are chemically tempered by means of an ion diffusion process, the improvement being obtained by decreasing the temperature at which the process is carried out during the course of the ion diffusion operation, by at least 40 * C.
Abstract: A process and apparatus for improving the properties of materials which are chemically tempered by means of an ion diffusion process, the improvement being obtained by decreasing the temperature at which the process is carried out during the course of the ion diffusion operation, by at least 40* C.

Journal ArticleDOI
TL;DR: In this paper, the three principal transformation structures of a Cr-Mo-V rotor steel which had been given a common tempering treatment were investigated and a single form of σ-έ-T relationship was obtained which can be derived from a solute-drag model.
Abstract: Creep tests have been carried out on the three principal transformation structures of a Cr-Mo-V rotor steel which had been given a common tempering treatment. Although creep strength varied with transformation structure, being lowest for martensite and highest for bainite, a single form of σ-έ-T relationship was obtained which can be derived from a solute-drag model.

Journal ArticleDOI
TL;DR: In this paper, the effect of thickness of a soft interlayer or specimen diameter on mechanical properties of welded specimens under static tension was investigated and the results were as follows: the yield stress and ultimate tensile strength increased and the elongation and reduction in area decrease as the relative thickness decreases, whereas the material of interlayer possesses high ductility under unidirectional tension at room temperature.
Abstract: In the welded joint, chemical composition and structure of weld metal or heat-affected zone which is adjacent to it are different from those of parent metal. Hence, the mechanical properties, for example stress-strain relation, of the welded joints must also be different from those of parent metal and change continuously. In this way, considering macroscopically, the welded joints are not homogeneous nor isotropic. Concerning such welded joints which are heterogeneous, it matters a great deal to investigate their strength and ductility. The welded joints are fundamentally idealized as models which are joints consisting solely of parent metal and a soft or hard interlayer. By "soft interlayer" is meant apart of welded joint in which yield point is lower than that of parent metal.In the present report, such model specimens were made by flash butt welding. The parent metal was grade S35C, the soft interlayer grade S10C. The specimens were given post-weld heat treatment (850°C×10 min. water quenching and 500°C×30 min. tempering) to cause an abrupt change of the mechanical properties between parent metals and soft interlayer. Static tensile test was made for four kinds of specimen diameter, 3, 6, 10 and 15 mm, at room temperature.In the joints including a soft interlayer under tension, plastic flow will begin at first in the parts of a soft interlayer. The transverse plastic flow of interlayer at the contact surfaces and the neighbouring zone will be held in check by the stronger parent metal, and the interlayer will be in a triaxial stress state analogous to that in the neck of tension specimen. The triaxiality will be severe with a decrease in the thickness of soft interlayer. The ultimate tensile strength of the joints exceeds that of the material of interlayer, if the values of thickness of interlayer are sufficiently low. The present paper describes theoretical and experimental investigations on the effect of thickness of a soft interlayer or specimen diameter on mechanical properties of welded specimens under static tension. The results obtained are as follows.(1) The yeild stress, ultimate tensile strength, plastic constraint factor and reduction in area of the welded joint including a soft interlayer are represented as functions of the relative thickness X, or the ratio of thickness of soft interlayer to specimen diameter, regardless of the specimen diameter.(2) The yield stress and ultimate tensile strength increase and the elongation and reduction in area decrease as the relative thickness decreases. Fracture mode becomes brittle for a sufficiently small value of X, although the material of interlayer possesses high ductility under unidirectional tension at room temperature.(3) The test results on ultimate tensile strength agree with the results of the authors' theoretical analysis for a comparatively large value of X.

Patent
19 Jun 1968
TL;DR: A heat-resisting alloy steel which is basically a 1 percent chromium-molybdenum-vanadium steel, with the addition of at least one element selected from the group comprising titanium, tantalum and niobium in the range from 0.03 to 0.15 total percentage by weight as discussed by the authors.
Abstract: A heat-resisting alloy steel which is basically a 1 percent chromium-molybdenum-vanadium steel, with the addition of at least one element selected from the group comprising titanium, tantalum and niobium in the range from 0.03 to 0.15 total percentage by weight, from 0.002 to 0.010 percent by weight boron and from 0.5 to 3.0 percent by weight cobalt. High-creep strength, rupture ductility and tensile strength properties are developed by austenitizing the steel in the range 950* C. to 1,060* C., hardening by cooling, and tempering in the range 600* C. to 700* C. for from 3 to 60 hours.


Patent
26 Jun 1968
TL;DR: A LEAF SPRING ELEMENT as discussed by the authors is made of CARBON STEEL HAVING A HIGH DEGREE OF FATIGUE and WEAR RESISTANCE, the springing ELEment being being HEAT TREATED SUCH that it has a RELATIVELY THIN SURFACE LAYER, OR RIM, of high HARDNESS and RelativELY HIGH RESIDUAL COMPRESSIVE STRESSES.
Abstract: A LEAF SPRING ELEMENT MADE OF CARBON STEEL HAVING A HIGH DEGREE OF FATIGUE AND WEAR RESISTANCE, THE SPRING ELEMENT BEING HEAT TREATED SUCH THAT IT HAS A RELATIVELY THIN SURFACE LAYER, OR RIM, OF HIGH HARDNESS AND RELATIVELY HIGH RESIDUAL COMPRESSIVE STRESSES. THESE PHYSICAL CHARACTERISTICS ARE PROVIDED BY QUENCHING THE SPRING ELEMENT AND THEN TEMPERING IT AT A TEMPERATURE SELECTED FROM WITHIN A RANGE OF APPROXIMATELY 300*F. TO 500*F., THE TEMPERING TEMPERATURE PREFERABLY BEING HELD FOR A RELATIVELY LONG PERIOD OF TIME.

Patent
13 May 1968
TL;DR: Weldable and magnetic ferritic malleable iron castings with an improved abrasion resistant wear layer are described in this article, and the method of forming such castings is described.
Abstract: Weldable and magnetic ferritic malleable iron castings having an improved abrasion resistant wear layer, and the method of forming such castings are described. The casing includes a body portion of full ferritic malleable iron which is covered with several zoned layers, viz., a pearlitic type matrix of broken spheroidized martensite which is partially depleted of carbon nodules, a decarburized wear layer of finely dispersed well distributed spheroidized carbides in a ferritic matrix which provides a good weld zone and an outer intergranular oxidation layer. In machining castings to be used for abrasion resistance the outer two layers and a portion of the wear layer are removed to expose the abrasion resistant wear layer. In the case of a casting to be welded, the outer layer and a portion of the weldable layer are removed. By controlling the structure of the casting between the fully ferritic body and the wear layer, high magnetic permeability and low magnetic remanance are obtained while providing a weldable casting. In forming such castings, white iron of malleable composition is annealed in a decarburizing atmosphere in which the ratio of carbon monoxide to carbon dioxide is closely controlled. The castings are heated to between 1800* F. and 1975* F. for a period of time sufficient to decompose the cementite followed by cooling to 1400* F. to 1650* F., and quenching or air colling, and tempering. Various details of the annealing and tempering cycles are described. rReference is made to U.S. application Ser. No. 605,955, filed Dec. 30, 1966, now U.S. Pat. No. 3,463,675 and assigned to the same assignee.


Patent
Akira Ujiie1
27 Mar 1968
TL;DR: A method of quenching and tempering including CONTROLLING the HEAT TREATMENT, CONTROILING the IMMERSION in a COOLING MEDIUM, and CONBOLLING REPEATED CYCLES to produce a STRONGER STEEL STRUCTURE is discussed in this article.
Abstract: A METHOD OF QUENCHING AND TEMPERING INCLUDING CONTROLLING THE HEAT TREATMENT, CONTROLLING THE IMMERSION IN A COOLING MEDIUM AND CONTROLLING REPEATED CYCLES TO PRODUCE A STRONGER STEEL STRUCTURE. D R A W I N G

Patent
26 Apr 1968
TL;DR: A process for treating vitreous materials to temper them which includes first chemically and then thermally tempering such materials is described in this article. But this process is not suitable for all materials.
Abstract: A process for treating vitreous materials to temper them which includes first chemically and then thermally tempering such materials.

Patent
19 Jun 1968
TL;DR: In this article, a heat resistant alloy steel which is basically a 1 percent chromium-molybdenum-vanadium steel with the addition of from 0.03 to 0.15 percent by weight niobium was developed.
Abstract: A heat-resistant alloy steel which is basically a 1 percent chromium-molybdenum-vanadium steel with the addition of from 0.03 to 0.15 percent by weight niobium and from 0.002 to 0.010 percent by weight boron. High hardenability and good high temperature ductility and creep properties are developed by austenitising the steel in the range 950* C. to 980* C., hardening by cooling to obtain a mainly bainitic structure, and tempering in the range 650* C. to 720* C. for at least 12 hours.

Patent
08 Jan 1968
TL;DR: In this paper, the alloy stretch is subjected to a final TEMPERING ANNEAL at a temperature in the range from 250*C. to 400*C, which is preferred to be conducted in a transverse magnetically determined domain.
Abstract: NICKEL-IRON-MOLYBDENUM ALLOY STRIP, OPTIONALLY INCLUDING COPPER, WHICH HAS PREVIOUSLY BEEN SUBJECTED TO AN ANNEALING TREATMENT AT A TEMPERATURE BETWEEN 950*C. AND 1220*C. IS ANNEALED AT A TEMPERATURE IN THE RANGE FROM 450*C. TO 600*C. AND RAPIDLY COOLED THEREAFTER TO IMPROVE THE INITIAL PERMEABILITY, THEN THE ALLOY STRIP IS SUBJECTED TO A FINAL TEMPERING ANNEAL AT A TEMPERATURE IN THE RANGE FROM 250*C. TO 400*C. WHICH IS PREFERABLY CONDUCTED IN A TRANSVERSE MAGNETIC DIELD STO IMPROVE INDUCTION RISE, $B.

Journal ArticleDOI
TL;DR: In this article, the best composition of high speed steel 11V9M3Kh3K6C was determined, which has a good combination of hardness, heat resistance, and strength: 1.08% C, 9.28% W, 3.48% Mo, 1.16% Si.
Abstract: 1. We determined the best composition of high-speed steel 11V9M3Kh3K6C, which has a good combination of hardness, heat resistance, and strength: 1.08% C, 9.28% W, 3.48% Mo, 1.55% V, 6% Co, 1.16% Si. 2. This steel has the highest hardness (HRC 69-69.5, which is 2-2.5 HRC units higher than that of the standard cobalt steels), high heat resistance (a hardness of HRC 60 is retained after 4h at 645°C, in contrast to the same hardness at 635°C for the standard cobalt steel R9K10), a strength of 200 kg/mm2, and an impact toughness of 3 kgm/cm2. 3. We worked out the following heat treatment for this steel: quenching from 1220±10°C, cooling in oil or a heated medium, tempering three to four times at 550–560°C for 1 h. 4. This steel should be widely tested for cutting, drilling, milling, and planing high-strength (including heat-resistant) steels and alloys without elevated dynamic loading.

Journal ArticleDOI
TL;DR: In this article, the authors found a correlation between the variations of line broadening, wear, and quenching temperature, which is due to austenite grain growth, and found that wear decreases with increasing quench temperature up to a certain limit.
Abstract: 1. An increase of quenching temperature followed by high-temperature tempering increases the resistance to slip; the optimal quenching temperature for steels 45 and 40 Kh are 1100°C with holding 20 min and 1000°C with holding 2 h, respectively. 2. An increase of quenching temperature for the steels investigated promotes an increase in the number of lattice defects, manifest in the increase of line broadening with peaks at 1100°C (holding 20 min) and 1000°C (holding 2 h). 3. On quenching followed by low-temperature tempering the wear decreases with increasing quenching temperature up to a certain limit. We found a correlation between the variations of line broadening, wear, and quenching temperature. 4. On quenching followed by high-temperature tempering the wear increases with the quenching temperature, which is due to austenite grain growth. The inherently fine-grained steel 30KhGT is an exception.

Journal ArticleDOI
TL;DR: In this paper, it was shown that the variation with temperature of the amplitude-dependent part of the internal friction due to carbon atoms is explained in terms of the average active dislocation loop length and the relaxation time.
Abstract: Cold working of tempered martensite affects the internal-friction peak height and the peak temperature, these effects being the reverse of those produced on tempering. The shift in peak temperature is explainable in terms of the average active dislocation loop length and the relaxation time. The variation with temperature of the amplitude-dependent part of the internal friction is thought to be attributable to change with temperature of the drag due to carbon atoms.

Journal ArticleDOI
TL;DR: In this paper, X-ray diffraction was used to study the effect of tempering of iron martensite particles at different temperatures from 200°C to 700°C.


Patent
08 Jan 1968

01 Feb 1968
TL;DR: In this paper, a literature survey was conducted to summarize the known effects of solid solution additions on the fracture toughness of high-strength steels and the results indicated that nickel is the singular alloy addition that consistently improves toughness while manganese has a detrimental effect.
Abstract: : A literature survey was conducted to summarize the known effects of solid solution additions on the fracture toughness of high-strength steels. The results indicate that nickel is the singular alloy addition that consistently improves toughness while manganese has a detrimental effect. In the range of compositions usually employed, variations in the percentage of carbide formers produces no well defined change in fracture toughness. Silicon has a marked effect on retarding the tempering reactions and some results indicate that when it is added to vacuum melted 4340 a significant increase in toughness can result. At present the use of secondary hardening mechanisms in the low alloy martensitic steels has not produced any significant improvement in toughness. (Author)