DE1621142A1 - Process for pickling copper-beryllium alloys - Google Patents

Description

Patent attorneys

Dipl.-Ing. Lamprecht

Munich 22, Steinsdorfstr. 10

503-1.2.468P 9-6.1967

PEOHIl ^- SY, Gompagnl © d @ Produits Chiml ^ es © t

, Paris

Method for barking Supfer-B © ryllium ~ Iiegl © riiBg © a

The invention looks at itself. on a Yerfahraß susa Belssa τοπ Kupf © r ~ BaryllIum-IiegIeruögeii _e It is not r »ar on alloys with 1.8" to 2 %> beryllium, which also contain shares of nickel or cobalt kSsn & en, senile on teraäre legisrungen with 0 , 4 to 0.7 # "beryllium. And 1.2 to 2.5 i> HIekel or 2 ₈ 3 to 2.7 # cobalt amread1> ar ·

Me torbrams made from these alloys ^ a, Sheets, sand and wires are always heat treated throw, are trots to report the surface O ^ di® The Metsall is covered by the security measures taken then with a thin layer of qacydech, which is difficult to remove and required a pickling treatment

The higher the pickling, the more difficult it is to carry out Quenching temperature is. Hence the pickle is the legislation with a relatively high cobalt or

505- (B1245) -TpF (0)

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solution heat treatment at a temperature of about 900 ° require, particularly arduous "

There are two methods of pickling copper-berylliua alloys generally used:

a) Pickling with an aqueous solution containing 20 50 vol. # sulfuric acid. Kau works between 40 and 60 ⁰ C with an immersion time between 10 minutes and an hour depending on the degree of oxidation of the metal

• κ about 850 g of water, 50 g of chromic acid and 150 carbons of Sehwef & lßätire

of 6Q ⁰ Be contains. This process is very slow and, in terms of the final appearance, is irregular _o In the case of the alloys Supfer ^ Eobslt-Beryllium, the pickling is incomplete

b) The chromosulfuric acid heating, which is carried out between 40 and 70 ° n in a bath, which contains 850 g of water, 50 g of chromic acid and 150 cm of sulfuric acid of 66 ⁰ Se anth & lt »Sas pickling requires about one minute and leads to an iron satisfactory surface condition, and This also applies to the copper-cobalt-beryllium alloys. Unfortunately, this procedure is very troublesome, as the bath deteriorates quickly as a result of reduction in the chromic acid it contains _{or the like}

BAD ORlGiNAt,

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The method of implementation of the invention is replacement the usual chemical Bsisbehaadlungea by an electrolytic bite, and swar la a w & sarigea solution which It contains a little bit of a potassium halide and a surface tension-active agent Apply copper beryl tom igieruageii with a thin Oxide layer are be & eokt as they are due to heat treatments arises »even if this occurs in an inert atmosphere carries out

The main advantages of this' Terfahrens are as follows: E is a fast retracts, which also good to ternary alloys old up to 2.7 f> cobalt or nickel, as in alloys bit 1,8 to 2 $ beryllium low cobalt or Kickelgehalts apply to l &ß; it gives the pickled part a good uniform metal appearance; the driving can easily be carried out continuously; it is also economical, because the electrolyte contains only simple and cheap components.

According to one embodiment of the invention one connects the metal to be pickled with the anode of a Equatorial generator, the cathode being an inert conductor is, e.g. non-oxidizable steel · The electrolytic bath. is a sodium chloride solution that contains a wetting agent, which is intended to facilitate the removal of the gray-black oxide

109823/13 55 BATHROOM

to favor the precipitation that forms at the moment of pickling. The wetting agent removes this precipitate. You can use an alcohol or a commercially available surface tension reactant which _{is compatible with the pH range specified below XBt 9.} It can be anionic, cationic or non-ionic.

Neither the bath concentration nor the working conditions of the temperature or the current density have to be within narrow limits * They can vary within wide ranges, without changing the results of the proceedings Concentration of sodium chloride between 100 and 200 g / l, the pH between 5.5 and 8.5 and the temperature between 20 and 45 ° · The clamping voltage is of the order of

2 ToIt and the current density between 3 and 5 amps. Per dm / The amount of wetting agent depends on its nature. if if you use methanol or ethanol, you need about 50 to 100 g / l. The surface tension active substances that are in the trade available Bind, is commonly used in a dose of 1 to 5 g / 1. The treatment time varies between 2 and minutes depending on the thickness of the oxide layer, after which the piece with Rinsed with water and dried.

The following examples are provided to illustrate the invention determined without restricting them.

BATH

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Example I.

Baader from a super beryllium aegierirag old 1.9 j £ beryllium and 0.3 jß cobalt were hardened in inert At & osp & Ire and then showed an oxidized Qb <etv £ lf, nhc ,, Maa pickles them in the continuous process aitteXs Bl? M '»ml? $ 9 in a bath containing 200 g / l HaQl and 70 ear Matamtol. The cathode consists of a plate made of aio & t-oxidizing steel and the anode consists of a metal strip that is fed through the bath at such a speed that the duration of the stay in the electrolyte is 3 meows. The clamping voltage is 2 ToIt and the current density is 5. Amp. Per dm. The tape is then washed in running »pure water and then dried. The metallic appearance is very even

Example II

Pieces made of an alloy of copper-Kobelt-Berylllum 2.5 and 0.5 ^ lobalt ί> beryllium, which in the course of negotiations ~ Wäraebe oxidized weren be attached to the anode and dipped in a bath containing 150 g / l VAOL and 2 g / l Celanol A contains «Dee Celano! Is the trade name of a surface-voltage neutral agent based on τοπ polyethoxy ether »

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10502371355

Bee Tesf ^ uree will feel 35 ° ait a for 10 minutes?

ψ®η 2 ToIt and a current density το »5 um Austibgeftnirt · AnsohlieSend the pieces © in

rinsed and dried · Ao preserved @@ 3s £ regular s ^ izung »which of the

There are noises.

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Claims (4)

.- 7 claims 1. Procedure »for the coating of copper-beryllium alloys with 1.8 to 2 # beryllium and possibly small proportions of nickel or cobalt as well as copper-cobalt-beryllium and cobalt-nickel-beryllium alloys with 0.4 to 0, 7 # beryllium and 2 _f 3 to 2.7 $> cobalt or 1.2 to 2 »5 # nickel, characterized in that the addition is carried out by means of direct current electrolysis, the alloy to be pickled being connected to the anode of a direct current generator, and that an aqueous alkali chloride solution with the addition of a surface tension active substance serves as the electrolyte « 2. The method according to claim 1 ,. characterized in that the Electrolysis bath 100 to 200 g / l sodium chloride and 50 to 100 g / l methanol or ethanol or 1 to 5 g / l one contain anionic, cationic or non-ionic surface tension active staffy 3. The method according to claim 1, characterized in that. the pH of the solution is between 5 »5 and 8.5 t its temperature between 20 and 45 ° and the terminal voltage is of the order of 2 volts, and dass.die current density 5 to ο
Is 5 amps per dm; 10-9 823/13 5 5 -BAD original 16211 * 2 4. The method according to claims 1 to 3 »characterized in that that the contribution is continuous or discontinuous for parts in the course of heat treatments In the course of the production of the metal, alloys oxidized is carried out. 109 823/1355