DE1433762A1 - Deterrent process - Google Patents

Description

Monsanto Chemical Company

800 North Lindbergh Boulevard, 66 St Louis, Missouri, USA

"Deterrent"

This invention relates to an improved method of quenching metals, particularly steel and more particularly an improved quenching process using a new two-phase quenching process.

The mechanical properties of the metals used in the manufacture of shaped articles, such as iron, copper, Nickel, aluminum, magnesium, zinc, gold, silver, and lead Tin and its alloys can be modified by various known methods of heat treatment, wherein the metal is heated to some specific temperature and then cooled. In many such heat

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The hot metal becomes action-procedures, more or cooled less rapidly, and such rapid cooling processes are commonly known as "quenching". In general, quenching is carried out by immersing the hot metal in a bath of liquid, like water or oil. A common quenching process is quenching steel in water or other aqueous liquids, or in oil.

Since steel is the most commonly quenched metal the following description refers to the present Invention primarily on steel, although it should be noted that such a process falls within the scope of the invention the described invention in no way restricts it.

Heating steel to high temperatures does the transformation of steel in austenite, a solid solution of carbon in surfaces centered cubic * Iron. On the subsequent rapid cooling (quenching), austenite transforms into martensite, one hard, brittle form of steel, which when in suitable Wise tempered, has the combination of strength and toughness usually inherent in steel. Cooling down in a slower manner than that which is used to

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Education before + fcartensit is required, hat the at temperatures above those with the Lkxrtensit bildur ^ connected, are, before. Auotenit; r.i .. 'eni ^ er .., ■: ■ wi'.nsej ten 3 tr u lit tu. * en, ..the mixtures of Iedrlit u.nd jB - .. i_: it üu

The H ^J 'rte einus Ütüiil3 in ICcrt sua: grjseten part of dora hollow ens toff content iea

Stahls at.iejieriui ^ s-forming 3 toffe ..voruen ^ u .rl

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A1t> lcuii.lunt, sv3rhält.nis to reduce, ua3 cjr required, ua siohorsuöteile, df.ss vollatandi ^ e:.: Atenüitatrwücturen are preserved. \ Tenn tsilv / eise ab ^ eachreck, iiinimt the A "bk" U: lverhj. '. Ltnis with the stinehmendera iJi.tf-imuj ^' inter di \ r Oi> erfl: iohe _# who are deterred. rope, off, out of this. The alloying elements control the alloying elements of a part, which can be atjeaohroofct into a complete line structure or, in other words, the ability of steel to join ^ 3times. The steels have a high degree of reliability and a part of the structure is not a losiUltniy.-nl'.uuiij lower jr-oliiuj ?. _The rate increases, but hollow places are expensive. On the other hand, cheap, -.venij-leji-irte or fully-Iiohlen- ^ e öti'hle require a higher one; hUhlun ^ aav.Bn ^ sc, ¹ ^ a d.is ^ a .. ^: rt <ir. in el-As. ^ e, j> 50u :: o. * i part, .. »jtjn their

9 0 3 SH / C ? 7 1

ORIGINAL

stronger quenching (higher decarburization rate) can warp and retainer cracks occur.

A deterrent process can conveniently be described as consisting of three stages:

1. In the first stage or steam cover stage is the Temperature of the metal so high that the Abs honor okuxedium is evaporated on the surface of the metal and a thin stable film of vapor surrounds the part. The steam coating acts as insulation and the cooling takes place primarily through radiation through the steam film. The cooling rate is relatively slow during this stage.

2. The second stage or steam boiling stage begins when the metal has cooled to such a temperature that the vapor film is no longer stable. The quenching medium then tends to wet the surface of the metal and vigorous boiling occurs. The heat will removed from the metal in a very rapid ratio as latent heat of vaporization. At this stage is the Cooling down the fastest.

3. The third stage or contact stage begins when the Surface temperature of the metal to the boiling point or -oereicli the liquid is decreased. Underneath

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the boiling stops and slow cooling takes place. Transmission or convection takes place. The cooldown ratio is lowest in the third level.

Water, water solutions, molten salts, C ¹ I and O 1 emulsions are some of the materials that have been used as Absehreek medißn so far. Although / barrels and containers solutions of inorganic salsa are the oldest and cheapest quenching media and give a maximum hardening capacity because they have the highest initial evacuation velocities, they have the disadvantage that the high Abaohreokgeso speeds lead to lower temperatures, which throw a 3 ± oh-throw _f Warping, cracking, uneven hardness and breakage as a result. The low boiling point of water is responsible for these properties.

If drain-off oils are used, the duration of the daiapfabdeok stage is longer; the cooling ratio in the boiling point is lower and that of the boiling point is shorter. Because of these properties, quenching with oils is far less drastic than quenching with water, because the transition from the second stage (boiling) to the third stage (licntakt-) is more gradual and the pulling forward is reduced. As a result, oil emulsions or different oils, v / ie Jisoh and "Marin" oil.

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animal oils, mineral oils and their mixtures, have in wide area of v / aaseous carrion back preparations displaced. Although the atsoureofcöle and oleiauisionen are, to a large extent, the internal stresses that arise during hardening, and although deterrence reduces the tendency to break -.- / ground, those in no-good conditions The stripped-off metals do not harden completely, as aie would do it if they were quenched in aqueous media, because of the exhaustion speed of such exhausting agents is much slower and in this way the formation of mixtures of the softer conversion products higher temperature allowed. In addition, oil and oil emulsions tend to oxidize to form sludge, thicken, collapse and decompose at elevated temperatures, which extends the life of such smoke evacuators significantly reduces it, makes it uncomfortable to use and produces results that are not uniform are. The combustible nature of the oils also stops severe pain in the experience of sucking oil and accordingly, it has long been after a substitute for oil absorbents wanted, but so far without much success.

Such an optimal suction cup preparation would have to be like this be that they have the cooling properties in the first suction stages of a strong deterrent, but in the lower temperature mountain Gioh, in which the Liartenait

809811/0271 BATH ORIGINAL 7 -

U33762

Transformation takes place the lower cooling ratio \ of a quenching agent of lower hardness, respectively! Has strength. The high initial cooling ratio would allow the use of low hardenability steels, while the low cooling ratio during transformation would reduce the thermal gradients that cause warping and cracking. In addition, the optimal quenching media would have to be in the work; be stable and fire resistant.

To get results that approach the results obtained by quenching with optimal Abeohreok preparations expected, previously proposed metal; Ie to harden in both water and oil in order to act on this Wise the advantage of the high Aoschreok ratio of water for the initial stages with the subsequent slower ones Quenching ratio of oil to perceive the desirable properties which are only obtainable with oil are received, S5U. However, in order to start with a two-phase preparation, which is composed of water and oil,

to harden, it is necessary to keep each phase in a separate Abeohreok tank, because using a single suction bath would cause the oil to float on the water, which would not bring any advantage. On the other hand, the λ use of two separate quenching tanks has many practical _ - _ BAD ORIGINAL

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tables l disadvantages, -, voloh-Q such an application form in have prevented the practice.

Sa is therefore an object of this invention that they a neu.ec and improved two-phase suction device * or preparation that is used when hardening Steel and other metal articles effective to an extent as is normally the case with aqueous quenching connected without being free, vun discard and xiiosbildung and other damages au renounce the C-χ of Differentiates between water as an exhaust medium. Eu is an object of this invention that it provides an improved suction process creates a corner preparation using a new two-line pipe.

It is also an object of this invention to provide a new and improved two-phaoene aspirin formulation which creates the advantage of ül ira in terms of the Quality of the hardened article, but which one is uneven Cl extrea is fire resistant and for this reason v / ünschenawerter than oil 13t. Heia · in3 single is going It is an object of this invention that it is a two-phase suction preparation creates, in which a phase is an aqueous phase, but the designated aqueous phase 'Phase is the upper- thcce.

ORIGINAL

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le is also an object of this invention that they provides a new quench formulation useful for use in heat treating metals, which has no fire risk, unpleasant smell, smoke or foam formation problems and which essentially Uniformly stable in the deterrent effect over a long period of use, durable, low in cost and can be used at different temperatures to achieve different advantageous quenching ratios to accomplish.

It has now been found that a two-phase quenching preparation, which the practical disadvantages of a water-and-oil system overcomes, but still retains the desirable properties of such a system is made by using an aqueous upper phase and a lower phase of chlorinated biphenyl. Such Preparation offers the advantage of an initial high speed aqueous quench with subsequent slow quenching in a ratio typical for oil quenching, with a quenching tank Can be used due to the fact that chlorinated biphenyl is heavier than water and a medium on which Is based on water and is therefore the lower phase. Other advantages of the new two-phase quench preparation are these Invention, as it will be seen below,

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sohlieseen gross fire resistance of the system, good stability against oxidation and thermal Influences, hydrolytic stability of the lower phase resulting in uniform exhaustion ratios. while a long period of time and a low cost. Another advantage is the two-phase preparation this invention allows the use of metals that can be obtained cheaply instead of expensive alloys, because the same hardening depth as with an oil suction extraction can be obtained, however, the undesirable results associated with an aqueous quench are like warping and icing, respectively Breakage, to be avoided. Likewise, the Zwei-Phaaen-Absohreokmltt.il of this invention can be used for box hardening and carburizing.

The suction process of this invention which uses the de-chewing line of this invention is a matter of course, ordered in dea immersion of a heated ketoll ax « into the oaere aqueous phase for a cor »· Duration and then in the immersion of the (lftgtfuitcftdt t » the lower chlorinated biphenylphae «· you time date that keeps an object in the aqueous phase, depends on the sons of the designated. Object, its composition and the desired depth of hardening, how this no oh described in more detail below v & rd <

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Wolter came to the. Control the extraction process as well by controlling both the aqueous and organic phase temperatures, even to the extent of the Incorporation of a soaking and tempering process can be obtained in one operation.

If one speaks of the immersion of an object in an extraction preparation, it is to be understood that there are various means of effecting this Zontakts, as they are commonly used by Paohmann, can be used. 3o, for example, the Sprayed water phase or you can use any phase over the '(Let rain, which is to be exhausted, flow.

orlertes biphenyl, which is from about 20 bia approximately 60% by weight of combined chlorine is generally for this invention useful, JβdoQh will QhZorlertea biphenyl, which β approximately 40 to 50 & ev * f (sebunApaes chlorine »

contains ι preferred, vat a JLbeohreekmediu »au aokaffea ^. which has the viscosity properties suitable for use at normal temperatures. Chlorinated biphenyl Commercially available borrowed in the form of products ■ which uaeefähr 2J ^ _t 32? C, 42jC, 483t _t _54jC or combined chlorine, corresponding approximately to mono-, di- or tri-, tetra- ,. pen ta and heia-Cfclorbiphanyl. The exceptions are "chlorinated bipiienyl, which is roughly

IBAD ORIGINAL " ¹² ~ P098t1 / 0i71

contains $ 40 to about $ 50 combined chlorine "/ and" chlorinated

Biphenyl, which contains from about 20 to about 60% combined chlorine "are used herein to include
not only lease these chlorinated products, but also mixtures of one or more of the chlorinated biphenyls, the total chlorine content largely in the range from $ 20 to $ 60, preferably in the range from $ 40
up to 50% by weight. For example, chlorinated biphenyl, which contains a total of 45% by weight of combined chlorine, for the purposes of this invention can be effectively prepared by mixing together
50 parts by weight of chlorinated biphenyl, which contains 42 parts by weight of combined chlorine and 50 parts by weight of chlorinated biphenyl, which contains 48% by weight of combined chlorine. In the same way, for further illustration, chlorinated biphenyl, which contains a total of 58 parts by weight of combined chlorine, can be prepared for the purposes of this invention by mixing together 25 parts by weight of chlorinated biphenyl, which contains 52 parts by weight of combined chlorine and 75 parts by weight .Parts of chlorinated biphenyl, which contains 60% by weight of combined chlorine. Thus, for the purposes of this invention, chlorinated biphenyl, which generally contains from about 20 _to about 60%, or preferably from about 40 to about 50% by weight of bound chlorine, can be obtained either by direct chlorination of biphenyl to obtain the desired bound chlorine content, obtain

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or a satisfactory material can be obtained by mixing two or more together
chlorinated biphenyls to obtain a resulting mixture of chlorinated biphenyls having an effective amount of combined chlorine in those indicated above
Contains areas.

The general physical properties of chlorinated biphenyl with varying amounts of bound Chlorine are given below.

-H-

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characteristic

52

chlorine
42

48

54

density

specific dish 25 ° / 25 ° C 1.18

(77 ° / 77 ° F) pounds per gallon 25 C

Initial boiling point 76O mm mercury, ⁰ C

Flash point open Clevelandsqhale ⁰ C

Cleveland Open ^{Bowl Focus 0} C 176.1

viscosity

Saybolt Universal 210 ° F (98.9 ° C) 30-31

Lake. (AS3K-D-88) 130 ° F (54.4 ° C) 35-37

100 ° F (37.8 ° C) 4Ο-Λ2

1.26

1.58

1.45

1.54

201.7

no

no

no

9.85 10 , 55. 11 t50 12.04 12.82 15.50 275 290 525 340 565 585 141.1-150 151 , 6-154, A. 175 , 6-180 192.8-195, no no , 6

no

31-52 34-35 36-57 44-48 72-78 39- ^ 11 Λ9-58 69-78 26O-34O 3 20CM 500 47-50 80-93 185-240 1800-2500 _

none means "no focal point up to boiling point"

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From the table it can be seen that chlorinated biphenyl It is considerable, heavier than water and heavier than a saline solution containing up to over $ 20 has a very high boiling point that it is never completely fire resistant and that the viscosities of chlorinated biphenyl offers a wide scope for different applications and process temperatures.

To understand the operation of the process of this invention and the uniqueness of the two-phase quenching thereof In order to explain the invention, two steels with significantly different properties, a steel with low hardenability AISI 104-6 and a steel with high hardenability, were used AISI 52100 by austenite formation and subsequent quenching heat treated according to the method of this invention in the novel quenchant of this invention.

The samples from each heat treated steel passed to Testing of hardenability on 1 inch and 2 inch diameter bars and for testing of warping on C-shaped bars Navy-type samples. Austenizing the test samples was in a controlled atmosphere furnace with a continuous influx of endothermic Gas (carbon monoxide / carbon dioxide) to prevent oxidation and To prevent decarburization carried out. A temperature of 1550 F was used for both steels and an ab-

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gas, dew point of 55 ⁰ F to -35 F, was "bez for AISI 1046th and AISI 52100 steel used .. The 1 inch Härtungsfähig ■ keitsstangen and deformation samples were heated for 1 hour in the oven, while the 2 inch Härtungsfähigkeitsstangen 2 hours have been heated for a long time.

The quenching procedure consisted of immersing the heated test samples in the water layer for various periods of time and then passing the samples into the chlorinated biphenyl layer. For the sake of simplicity, chlorinated biphenyl containing 42% by weight of bound Chlox * was used. The quenched bars, tested for hardenability, were cut transversely down the middle of the length (length equal to 4 times the durometer) with a grinding wheel and a transverse cut approximately 5/8 inch thick was removed. Approximately 0.030 to O ₉₀₄₀ inch were then removed from the surfaces which should be investigated so that any combustion (heat treatment), originating was removed from the Aufschneidstufe}. Each sample was tested for burn-off by etching in 5% nitric acid for 15 seconds, followed by 15 seconds in 10% hydrochloric acid. No burn was found on any of the samples.

Hardness crosspieces were made through transverse sections

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with Rockwell C hardness readings with 1/16 inch spaces made across at least two diameters. The results of the hardenability tests at 1 inch AISI 1046 rods (averages) are plotted in and upon viewing of drawing 1 it can be seen that the hardening is essentially the same as that in the case of direct water quenching (4 minutes) was obtained with samples immersed in water for 16 seconds, subsequently quenched in chlorinated biphenyl. The same results were obtained with 2 inch rods as in Drawing 2 shown received. The results of the hardening ability tests for 1 inch and 2 inch AISI 52100 rods (average values) are in the drawings 3 and 4, from which it can be seen that with 1 inch samples of this steel the complete hardening with all combinations of water-chlorinated-bi] / enyl-quenching and that for 2 inch samples, quenching in water for 32 seconds followed by chlorination Biphenyl, an approximately equivalent hardening of a complete water quenching (3, respectively 5 minutes).

In the deformation investigations, an optical scale was used to measure the opening width before and after the Measure heat treatment. The difference in these fine

the values is the amount of deformation. The results

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of the deformation investigations (average values) recorded in drawing 5, from which it can be seen that the deformation is considerable when using fixed water-chlorinated-biphenyl-AOhorse is reduced and that also no cracking in the time-determined water-chlorinated-biphenyl-quenching was observed.

Although direct comparisons between the results of the hardenability tests and the deformation tests are difficult to make due to the large differences in the size of the cut, it is noteworthy that the maximum achievable hardening for AISI1O46 steel
water-chlorinated biphenyl quenching in 16 seconds
was obtained, but with reference to drawing 5 is
it can be seen immediately that the deformation resulting from such an order was considerably less than
those, which in the case of deterrence for a longer period of time in
Water was obtained. In the case of AISI 52100 steel, the test results also show that there is a reduction in fortification. without a corresponding loss of hardness, by using a time-limited water-chlorinated-biphenyl-drawer.

Because it is known »that the barrier is in salt water is heavier than quenching in water, that is

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because the cooling ratio of an object to be set is faster in saline than in water, hardenability tests were done on 2 inch. diameter Hardening bars made of AISI 1046 steel, using a temporary saline solution-chlorinated-biphenyl-quenching was applied. The saline solution used was a 9% sodium chloride solution. The heat treatment process was the same as described above. The results of these investigations are in drawing ~ Figure 6 shows, from which it can be seen that the maximum hardening depth with a 12 second salt solution chlorinated biphenyl quenching was obtained / i. Data from the research studies showed that lower Deformation at 12 seconds of saline-chlorinated-biphenyl-exhaustion against deterrents from prolonged immersion in saline solution. It is important, however, that no deterrent cracks have been observed. Similar results were typical with other Saline repellants, such as those which Containing 6 to 12 # sodium chloride.

Aue the results of the time-limited water-chlorinated tea-biphenyl deterrent and the saline-chlorinated-biphenyl-exhaustion it can be seen that the present invention when including the use of a 2-phase Abschreok preparation, composed of one

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upper aqueous layer and a lower chlorinated one Biphenyl layer, a procedure creates with one improved means for quenching metals, with a large increase in hardenability *: without expected deformation, Cracking and the like, is realized.

Chlorinated biphenyl, as described above, comprises a larger proportion of the lower or organic phase the two-phase quench formulation of this invention and it is generally used for fire prevention purposes preferred that chlorinated biphenyl at least

. essential

50? O and even more desirably comprises all of the lower phase of the inventive quenching medium. It is contemplated, however, that within the scope of this invention the two-phase quenchant may comprise an upper aqueous phase and a lower homogeneous phase composed of mixtures of chlorinated biphenyl and oil, for example, fish oils, "marine" Oils, animal oils and mineral oils or other materials whose mixtures still have a density that is noticeably greater than the aqueous phase at the working temperature of the preparation «An example of the physical properties of typical mineral oil-chlorinated biphenyl mixtures that have a suitable density, is

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indicated in the table below. The oil had the following properties:

API severity
Viscosity ■
Flash point ⁽ 22 to 23
160
545 äl specific weight Pounds / gal. - 210 ° ( Physical properties of the oil-chlorinated biphenyl gels 50
25th 1.1263
1.2703 9.4
10.6 3 sus Weight percent chlorinated biphenyl
$ 48 chlorine 50
75

In addition, other chlorinated aliphatic ^ and aromatic hydrocarbons such as trichlorobenzene, chlorinated terphenyl and chlorinated naphthalene with chlorinated Biphenyl can be mixed to form the lower phase of the two-phase Abschreok formulation of this invention create. In particular, the use of trichlorobenzene is in an amount up to about $ 10-15 the chlorinated biphenyl content of the organic phase is particularly desirable when the quenching process is under Low temperature conditions are carried out should, because the viscosity of the resulting mixture at low temperatures is noticeable by such a

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application is reduced trichlorobenzene without .to cause undoubtedly undesirable decrease in ä.en other properties of the organic phase.

It is readily apparent that either the aqueous Phase or the organic phase or both phases of the two-phase quenching agent according to the invention may contain various functional additives such as quench rate modifiers, Viscosity modifiers, wetting agents, antioxidants, rust inhibitors, flow agents or Droplet point depressants and the like, such as organic sulfonates, fatty acids, amines, silica sols, Ethylene or propylene oxide polymers high Malekulargewiohts, soluble resins, or mucilages, such as carboxy-methyl-cellulose, methyl-cellulose and hydroxy-ethyl-cellulose, lerpen polymer resins, heat-treated vegetable oils, residues from the petroleum. Refining, partially oxidized petroleum hydrocarbons, Alkylphenol-ethylene oxide condensation products, Alkylphenol-polyethylene-glycols, sodium-alkyl-sulfates, Polyoxyethylene esters of tall oil, organic sulfonates, for example, sodium sulfonate, barium and calcium sulfonate, Metal naphthenates, reaction products of organic Sulfonates and a phosphorus sulfide, reaction

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products of a phosphorus sulphide and an organic one Amine, mono-, di- and triethanolamine, sodium-f potassium or Ammonium borate, linolenic acid dimers and others Fatty acids, the reaction products of an alkenylberastinic acid anhydride, aliphatic acid and polyalkylene polyamine, Phosphites, and phenyl-alpha-naplithylamine.

It goes without saying that this invention, although made only with regard to various specific examples and embodiments have been described is not limited to such examples and embodiments and that it can be implemented in the most varied of ways within the scope of the following patent claims.

ORIGINAL INSTECTED

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Claims (10)

Claims 1. Two-phase quenching preparation characterized in that that it includes a) an upper aqueous phase and b) a lower phase chlorinated biphenyl, which from
contains about 20 to about 60 parts by weight of combined chlorine. 2. Two-phase quenching preparation characterized, that it includes a) an upper aqueous phase and b) a lower phase chlorinated biphenyl, which from
contains about 40 to about 50 weight percent bound chlorine. 3. Two-phase Abschreok preparation - characterized in that that it includes a) an upper water phase and b) a lower phase chlorinated biphenyl, which from
Contains about 40 to about 50 weight percent combined chlorine. 4. Two-phase quenching preparation characterized in that that it includes a) an upper saline phase and b) a lower phase chlorinated biphenyl, which from
contains about 40 to about 50 weight percent combined chlorine. - 25 809811/0271 U33762 5. Zwei-Elia ^ en-Absdhreck preparation, characterized in that that includes them a) an upper aqueous phase and b) a lower phase on chlorinated biphenyl, which about 20 to about 60 wt. $. combined chlorine and Contains oil. 6. ' Process for quenching metals in one Two-phase deterrent preparation according to claim 1 characterized in that it involves immersing a heated metal object in the upper aqueous phase for a time sufficient to partially quench said heated object and the immersion of said article in the lower chlorinated biphenyl phase. 7. A method for quenching metals in a two-phase straightening preparation according to claim 2 characterized in that it involves immersing a heated metal object in the upper aqueous phase for a time sufficient to partially quench said heated object and then the immersion of said article in the lower chlorinated biphenyl phase. 8. Process for quenching metals in one - 26 - 809811/0271 Two-phase ADsohreetoirigszubereitiZHg · according to claim. 4-thereby marked * that the steps are immersion of a heated metal object in the upper water Phase for a time that is sufficient to partially frighten the said heated object and then immersing said object in the lower one chlorinated biphenyl phase. 9. A method for quenching metals in a two-phase quenching preparation according to claim 5 characterized in that it includes the steps of immersing a heated metal object in the upper aqueous phase for a time sufficient to produce said partially quenching the heated object and then immersing the said object in the tere chlorinated biphenyl phase includes. 10. Invention-essentially as described here and claimed. 8098T1 / 0271