EP0100280B1 - Abschreckbad und Verfahren zum Abschrecken von Metallen - Google Patents

Abschreckbad und Verfahren zum Abschrecken von Metallen Download PDF

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Publication number
EP0100280B1
EP0100280B1 EP83401521A EP83401521A EP0100280B1 EP 0100280 B1 EP0100280 B1 EP 0100280B1 EP 83401521 A EP83401521 A EP 83401521A EP 83401521 A EP83401521 A EP 83401521A EP 0100280 B1 EP0100280 B1 EP 0100280B1
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EP
European Patent Office
Prior art keywords
weight
hah
bath
quenching
hydrogenated starch
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP83401521A
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English (en)
French (fr)
Other versions
EP0100280A1 (de
Inventor
Serge Gosset
Michel Huchette
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Roquette Freres SA
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Roquette Freres SA
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Filing date
Publication date
Application filed by Roquette Freres SA filed Critical Roquette Freres SA
Priority to AT83401521T priority Critical patent/ATE25110T1/de
Publication of EP0100280A1 publication Critical patent/EP0100280A1/de
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Publication of EP0100280B1 publication Critical patent/EP0100280B1/de
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/56—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering characterised by the quenching agents
    • C21D1/60—Aqueous agents

Definitions

  • the present invention relates to an aqueous bath for quenching ferrous and non-ferrous metals and their alloys. It also relates to the process for tempering metals using said bath.
  • the transformation law can be expressed as follows: for there to be quenching, it is essential that before the above-mentioned cooling the critical point corresponding to the end of the transformation due to heating is exceeded and that the temperature of the metal either such that it is completely in the stable state when hot.
  • the temperature zone corresponding to the desired structure that is to say at the point of equilibrium where the solubility of the various constituent elements is maximum, is sometimes between very little apart limits l ' one of the other.
  • the actual quenching is carried out, that is to say a more or less rapid cooling depending on the alloy and the kind of room ; the molecular distribution of the hot stable state is thus kept cold, which makes it possible to advantageously modify the mechanical characteristics of the alloy.
  • liquids used for quenching are therefore very varied: cold water, water containing sodium chloride or soda, lime water, acid water, hot water, petroleum, oils, tallow, and more recently water and polyvinyl alcohol , water and polyalkylene glycols.
  • quenching is a meticulous operation which requires a lot of precautions.
  • suitable quench baths capable of varying the cooling rate within the desired limits should be used in order to obtain the desired characteristics.
  • the quench bath according to the invention is characterized in that it comprises an aqueous solution of a hydrogenated starch hydrolyzate having a percentage by weight expressed on the dry matter of polymerization products 1 and 2 between 1 and 90, the complement to 100 being constituted by polymerization products equal to or greater than 3, the percentage by weight of reducing sugars comprised by this hydrolyzate being less than 5%, preferably less than 2% and more preferably still less than 0.5%, the concentration of the bath in said hydrolyzate of hydrogenated starch being from 0.2 to 80% by weight.
  • the starch can be hydrolyzed, by the acid route, by the enzymatic route or by the mixed acid-enzymatic route, to different degrees, the degree of hydrolysis being generally characterized by the Dextrose-Equivalent (DE) defined as being reducing power of the hydrolyzate, expressed in D-glucose and related to dry matter.
  • DE Dextrose-Equivalent
  • starch hydrolysates of different EDs and having a very varied distribution of products of different degrees of polymerization: glucose ( DP 1), maltose and isomaltose (DP 2), maltotriose (DP 3), oligosaccharides and polysaccharides.
  • the starch hydrolysates of varied composition thus obtained can then be hydrogenated, in a manner known per se, generally under hydrogen pressures and at high temperatures and in the presence of catalysts such as, for example, Raney nickel.
  • catalysts such as, for example, Raney nickel.
  • the various sugars constituting the starch hydrolyzate are thus transformed into corresponding polyols.
  • the hydrogenated starch hydrolyzate applied in accordance with the invention has a percentage by weight of products of DP 1 and DP 2 of between 2 and 75%, and more preferably still of between 2 and 65%, the complement to 100 being constituted by products of DP greater than or equal to 3.
  • the preferred hydrogenated starch hydrolysates are obtained by hydrogenation of starch hydrolysates having a DE of between 15 and 70.
  • HAH hydrogenated starch hydrolyzate
  • the quenching bath in accordance with the invention had performances significantly superior to those of aqueous quenching baths of the prior art mentioned above and comprising polyhydric alcohols selected in the group consisting of sorbitol, mannitol, maltitol and lactitol; these baths had previously been considered satisfactory.
  • the properties of the quench bath according to the invention vary according to the chosen concentration of HAH.
  • Baths with an accelerating effect contain from 0.2 to 40% and preferably from 0.5 to 35% by weight of HAH.
  • Baths having a cooling rate retarding effect compared to water contain 40 to 80%, preferably 40 to 75% by weight of HAH.
  • the quench bath according to the invention comprising from 0.2 to 80% by weight of HAH, can be used at temperatures varying in particular from 4 to 60 ° C, preferably from 4 to 50 ° C and more preferably still from 10 to 45 ° C.
  • the HAH forming part of the quenching bath according to the invention not only modifies, as indicated above, the cooling rate of the quenched metals, but also has other advantages. First of all, it does not exhibit aggressiveness with respect to metals and their alloys and can, on the contrary, even have a protective effect on surfaces. It avoids in particular the granular corrosion of aluminum alloys, corrosion which is formed in particular in quenching baths containing compounds of mineral origin such as sodium or potassium derivatives whose aggressiveness both with respect to ferrous alloys and light alloys is important.
  • the hardness imparted to the parts treated in accordance with the invention is greater than that of the parts treated conventionally, for example by water quenching.
  • Another advantage lies in the non-toxicity of the hydrogenated starch hydrolysates used in the quench bath according to the invention, in their perfect biodegradability as well as in their non-flammability.
  • the hydrogenated starch hydrolyzate one or more oxyanion salts chosen particularly from those comprising tin, germanium, tellurium , arsenic and, preferably, boron, these salts being capable of forming, with the hydrogenated starch hydrolyzate, complexes soluble in water.
  • HAH (MS) / salt ratio is chosen between 100/1 and 1/2 and more preferably between 30/1 and 1/1.
  • these salts are dissolved in the hydrogenated starch hydrolyzate syrup and allowed to react with the latter before the formation of the baths.
  • the quench bath according to the invention can also contain various adjuvants such as antioxidants, anti-corrosion agents, bactericidal agents, and the like.
  • adjuvants such as antioxidants, anti-corrosion agents, bactericidal agents, and the like.
  • a CETIM drasticimeter (Technical Center of Mechanical Industries SENLIS-FRANCE) constituted by a silver cylinder of revolution, of diameter equal to 8 mm and length equal to 24 mm, is brought to a temperature of 800 ° C and is then plunged abruptly in an unstirred 200 cm 3 quench bath.
  • we start recording temperature 6 (in ° C) as a function of time t (in seconds) and we draw the curve 0 f (t).
  • a control curve is produced with a bath consisting solely of distilled water, at a temperature of 30 ° C.
  • the quenching fluid now consisting of a 5% by weight solution of dry matter of a hydrogenated starch hydrolyzate (HAH 1) in water. distilled.
  • This HAH 1 hydrolyzate was prepared from a starch hydrolyzate whose DE before hydrogenation was 55 and which itself had previously been prepared by double enzymatic hydrolysis, with ⁇ -amylase then with ⁇ -amylase.
  • the percentage by weight of reducing sugars of the hydrolyzate HAH 1 is less than 0.20 and its composition (in% by weight on dry matter) as follows:
  • This example is a comparative example of the performances obtained with the hydrolyzate HAH 1 and two other hydrogenated hydrolysates HAH 2 and HAH 3, prepared by hydrogenation of starch hydrolysates of different composition having before hydrogenation EDs of 33 and 30 respectively.
  • composition of the HAH 2 and HAH 3 hydrolysates was as follows:
  • Example 2 The conditions of the tests were identical to those of Example 1, the quench baths tested containing respectively 5% of each of HAH 1, 2 and 3 and their temperature being 30 ° C.
  • This example was carried out to compare the performances recorded for the acceleration of the cooling rate, on the one hand, in the case of a quench bath according to the invention and, on the other hand, in the case of two quenching baths according to the prior art.
  • the quench bath according to the invention consisted of a solution at 5% by weight of m. s. HAH 2 hydrolyzate in distilled water.
  • the performances obtained in the case of the hydrolyzate HAH 3 are compared with those obtained in the case of the same hydrolyzate in which borax had previously been dispersed in a proportion of 10% of borax decahydrate (percentage expressed in matter as is on the dry matter of the hydrolyzate).
  • the quench baths were at a concentration of 5% by weight of m. s. and at a temperature of 30 ° C.
  • borax slightly modifies the cooling rate obtained using the hydrolyzate alone.
  • Drasticity curves were therefore established in the same manner as above with quench baths containing 5%, 10% and 20% by weight (dry matter) of the HAH 3 hydrolyzate, respectively.
  • the temperature of a quench bath can be maintained at around 30 ° C, but in reality the variations can range from a temperature of about 10 ° C, for a "fresh" quench bath, to 60 ° C approx., For a very stressed quench bath if vigorous temperature control is not used.
  • the hydrogenated starch hydrolyzate used corresponds to that identified in Example 2 by HAH 3.
  • the parts treated by the so-called poteyage method are cast aluminum alloy parts of the AU 5 GT type.
  • the bath is at room temperature.
  • the duration of the immersion is 8 minutes.
  • the hardness generally required for quenched parts is at least 80 HB, a value which is just obtained by conventional quenching with water.
  • the purpose of this example is to illustrate the retarding effect exhibited by the baths according to the invention when their concentration is high.
  • the bath temperature was always 30 ° C.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Physics & Mathematics (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Devices For Conveying Motion By Means Of Endless Flexible Members (AREA)
  • Magnetic Heads (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Heat Treatment Of Articles (AREA)
  • Compounds Of Iron (AREA)
  • Polyurethanes Or Polyureas (AREA)

Claims (11)

1. Abschreckbad für Eisenmetalle, Nichteisenmetalle und ihre Legierungen, dadurch gekennzeichnet, daß es eine wässerige Lösung eines hydrierten Stärkehydrolysats enthält, das einen Gewichtsprozentsatz, bezogen auf Trockenmaterial, von Produkten mit einem Polymerisationsgrad von 1 und 2 zwischen 1 und 90 enthält, wobei der Rest auf 100 aus Produkten mit einem Polymerisationsgrad von 3 oder darüber gebildet ist, wobei der Gewichtsprozentsatz der in diesem Hydrolysat enthaltenen reduzierenden Zucker kleiner als 5 % ist und die Konzentration des Bades an diesem hydrierten Stärkehydrolysat 0,2 bis 80 Gew.-% beträgt.
2.' Bad nach Anspruch 1, dadurch gekennzeichnet, daß der Prozentsatz an reduzierenden Zuckern unter 2 Gew.-% beträgt.
3. Bad nach Anspruch 1, dadurch gekennzeichnet, daß der Prozentsatz an reduzierenden Zuckern unter 0,5 Gew.-% beträgt.
4. Bad nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß der Gewichtsprozentsatz an Produkten mit einem Polymerisationsgrad von 1 und 2 zwischen 2 und 75 beträgt.
5. Bad nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß der Gewichtsprozentsatz an Produkten mit einem Polymerisationsgrad von 1 und 2 zwischen 2 und 65 beträgt.
6. Bad nach einem der Ansprüche 1 bis 5, in welchem die Konzentration an hydriertem Stärkehydrolysat 0,2 bis 40 Gew.-% beträgt.
7. Bad nach einem der Ansprüche 1 bis 5, in welchem die Konzentration an hydriertem Stärkehydrolysat von 0,5 bis 35 Gew.-% beträgt.
8. Bad nach einem der Ansprüche 1 bis 5, in welchem die Konzentration an hydriertem Stärkehydrolysat von 40 bis 80 Gew.-% beträgt.
9. Bad nach einem der Ansprüche 1 bis 5, in welchem die Konzentration an hydriertem Stärkehydrolysat von 40 bis 75 Gew.-% beträgt.
10. Bad nach einem der Ansprüche 1 bis 9, dadurch gekennzeichnet, daß es neben dem hydrierten Stärkehydrolysat wenigstens ein Salz eines Oxyanions, ausgewählt unter jenen, die Bor, Zinn, Germanium, Tellur und Arsen umfassen, enthält.
11. Verfahren zum Abschrecken von Eisenmetallen, Nichteisenmetallen und ihren Legierungen, dadurch gekennzeichnet, daß man das Metall, das zuvor auf eine Temperatur gebracht worden ist, bei welcher es die gewünschte Struktur aufweist, in ein wässeriges Bad gemäß einem der Ansprüche 1 bis 10, dessen Temperatur von 4 bis 60 °C beträgt, eintaucht.
EP83401521A 1982-07-23 1983-07-25 Abschreckbad und Verfahren zum Abschrecken von Metallen Expired EP0100280B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83401521T ATE25110T1 (de) 1982-07-23 1983-07-25 Abschreckbad und verfahren zum abschrecken von metallen.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8212921A FR2530668B1 (fr) 1982-07-23 1982-07-23 Application d'un hydrolysat d'amidon hydrogene a la trempe des metaux
FR8212921 1982-07-23

Publications (2)

Publication Number Publication Date
EP0100280A1 EP0100280A1 (de) 1984-02-08
EP0100280B1 true EP0100280B1 (de) 1987-01-21

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Family Applications (1)

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EP83401521A Expired EP0100280B1 (de) 1982-07-23 1983-07-25 Abschreckbad und Verfahren zum Abschrecken von Metallen

Country Status (11)

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US (1) US4441937A (de)
EP (1) EP0100280B1 (de)
JP (1) JPS5935617A (de)
AT (1) ATE25110T1 (de)
AU (1) AU542742B2 (de)
BR (1) BR8303929A (de)
CA (1) CA1232828A (de)
DE (1) DE3369345D1 (de)
ES (1) ES524360A0 (de)
FR (1) FR2530668B1 (de)
ZA (1) ZA835377B (de)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2671103B1 (fr) * 1990-12-27 1994-05-13 Roquette Freres Composition, bain et procede de trempe des metaux.
EP0699242B1 (de) * 1993-05-18 2000-07-12 Aluminum Company Of America Verfahren zur wärmebehandlung von metall mit kühlung in einer flüssigkeit mit darin aufgelöstem gas
US6689227B2 (en) * 2001-01-23 2004-02-10 Tata Consultancy Services, Division Of Tata Sons Ltd Eco-friendly starch quenchants

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US710452A (en) * 1902-05-15 1902-10-07 Mary J R Greenman Process of hardening metals.
US2115828A (en) * 1935-04-13 1938-05-03 Bell Telephone Labor Inc Electron emitting cathode and method of preparation
US2770564A (en) * 1954-07-06 1956-11-13 Gordon Mack Method of quenching metals
FR1167785A (fr) * 1956-11-13 1958-11-28 Procédé pour la trempe des métaux
US3022205A (en) * 1958-05-14 1962-02-20 Gen Motors Corp Method of quenching and quenching liquid
US3220893A (en) * 1963-11-29 1965-11-30 Union Carbide Corp Metal quenching medium
FR1384244A (fr) * 1963-12-26 1965-01-04 Union Carbide Corp Milieu de trempe d'un métal
US3475232A (en) * 1966-11-23 1969-10-28 Houghton & Co E F Method of quenching
US3526551A (en) * 1968-01-17 1970-09-01 Herbert Sargent Process for heat treating metals
JPS5130695B2 (de) * 1972-08-25 1976-09-02
JPS5373406A (en) * 1973-12-17 1978-06-29 Kanto Yakin Kogyo Kk Quenching media for steel
US4192764A (en) * 1977-11-03 1980-03-11 Western Electric Company, Inc. Stabilizing composition for a metal deposition process
DE2909697A1 (de) * 1978-03-14 1979-09-20 Centre Rech Metallurgique Verfahren zur oberflaechenbehandlung von metallband

Also Published As

Publication number Publication date
EP0100280A1 (de) 1984-02-08
DE3369345D1 (en) 1987-02-26
FR2530668A1 (fr) 1984-01-27
ATE25110T1 (de) 1987-02-15
CA1232828A (en) 1988-02-16
ES8403973A1 (es) 1984-04-16
JPS5935617A (ja) 1984-02-27
ES524360A0 (es) 1984-04-16
AU1726283A (en) 1984-01-26
AU542742B2 (en) 1985-03-07
ZA835377B (en) 1985-02-27
FR2530668B1 (fr) 1987-05-07
BR8303929A (pt) 1984-02-28
US4441937A (en) 1984-04-10

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