DE1533156A1 - Powder mixture and process for the production of dispersion hardened lead - Google Patents

Description

KOPi I

PATENT ADVERTISEMENT "" ■ ^m ^ "^ ■ tt M * tai, (tan; DIPL-ING. ERICH SCHUBERT 1533156 ** · - **., ****.

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Abu raMntamra "Ο ^, - Ικ". SCHUUXT, 5 »Sm ₀ M, Ειμπμτ Srrau * JJT Drnhd» lenk AG.,

Branches Sivgm u..Ob «ihaus« n (RhId.)

014 Dr.Btt / y » 20th May 1966

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909881 / 040-2 ^ obkbnal

wleiit. A particularly »effective deformation proxy is there · Extrusion that takes place at room temperature or a slightly higher temperature Executed in powder below the peeling point of the lead will.

As a result of the conductivity with which the lead oxide is formed on the powder particles and can then be dispersed in the deformation process, the production of diapersion-hardened lead in this way is relatively simple and economical. However, the presence of free lead oxide, which in the generally accepted sense is not a ceramic material, brings with it the tenders, a certain susceptibility to corrosion, so that in this respect the product may be less than ordinary lead. In addition, the carbon deposits generally contain a certain amount of lead carbonates which is associated with them or assigned to them, and this can lead to a? ! © igimg äss Products «for puffing up (caused by carbon dioxide stasete dia feadigQb®

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1/0402

BATH ORIGINAL

of lead powder and ceramic oxide Degree of dispersion when avoiding premature agglomeration of the lead particles due to their inherent softness and suppleness attributed to let.

The inventive method for producing dispersion hardened Lead consists of the stages of movement dt intimate Kleenex »of lead powder and a smaller proportion of a ·· ceramic oxide powder in βiner oxidizing, preferably Oxygen atmosphere that covers the lead parts with lead oxide and thereby the agglomeration of these by the action the pressure verification prevents while a substantially Obtained smooth dispersion of the ceramic oxide the subject of this mixture to a reduction process for the chemical reduction of most of the lead oxide, preferably not to the ceramic oxide because of the greater stability of the latter, and subjecting the powder mixture thus reduced to a deformation process in order to Lead particles in a coherent matrix with that everywhere to amalgamate ceramic oxide dispersed therein. Sa the Heduction process below the acidic melting point of lead (purpose Maintaining the powder form) must be carried out, the reduction of the total lead oxide and at the same time the dee lead carbonate, that tends to be present with this one doesn't easy to do. However, the presence of only a small amount of lead oxide and lead carbonate in the powder signifies that.

909881/0402 bathroom original

mixed, if this dta is subjected to deformation proofs «and hence in the end product that the "receptivity of the end products" compared to corrosion and / swelling only correspondingly low • a can.

In the execution or application of the invention,

I was drawn to the use of a ceramic oxide powder with submicron particles, while the lead powder » particles in the majority have a uniform grain size of can be about 50 microns or less. So I put it out, that a ratio of about 100 ι 1 »between the duroheo-ethical Lead part size and average Particle size of the ceramic oxide already gives good results, but this is not a Greaavert, and even better results are available with a different ratio, especially if lead powder; a with a considerably smaller grain size easily su get let.

Ee is still sucked vertically in the implementation of the invention, the lead powder and the ceramic oxide powder by ball grinding * u "laugh, which other misohver * r like Yibrationeci!" Chen or mixing at high speed, is sucked in "During ball grinding * when amalgamate the Eleiteilohen to su., especially f? "ch lj.egen _(this does not wnn öurch counterpart d 'r oxidizing atmosphere prevents wtirdft, untsjr raises the Kug"). In the filling WDiIe di # oxidumhUllteii Bl "it" ll »c hers elD ^ ^v ^ t * - ··· _: De format ion, atanet hitrb ^ j. (You iot; <[»rdt * hurry»

BATH 0 9 8 81/0402

into the lead, and so brings tin particularly homogeneous oil emerge from the a.; Trangpreflprodukt alt more even distribution the ceramic oxide is obtained.

This preference of Kugelveraahlena as Misohjprozefl is zurüokeufUhren to an experiment in which this Prosefl was old and compared vibration niches with hochtourigem Misohen · For these and other attempts "is how yet been received, lead powder was used, the lead old 99.97 i Purity and a nominal particle size of up to 300 mesh (ie less than 53 microns) was made by "atomization". Jedoon, a "grain analyst of the powder" concluded that about 60 parts by weight of the particles "were between 30 and 50 microns. The powder" as received "had a lead oxide content of about 1.35 crew weight percent calculated as PbO * Las ceramic oxide powder used was Öaraaa aluminum oxide with a reported particle size in the range of 0.030-0.005 microns.

(Attempts to grind aluminum oxide powder of this grain size even further by ball grinding, for the purpose of obtaining an even smaller grain size which could have an even greater effect on the dispersion hardening, were in fact unsuccessful in the case of lower hardening values. final product. Ee seemed ala agglomeration had occurred rather than the further fragmentation of alumina, possibly Infol ₀ e of the structure of electrostatic charges aif the insulating particles.)

BATH ORIGINAL

909881 / 0Λ02

Pur the Veröleicheverauche of the different Miachproseeat an addition of 2 percent by volume of the alumina powder to the lead powder was used,

For the Vitrationemiachunt, β me YibrationskugelaUhl * It has a stainless steel container and no balls are used. Batches of 298 g of lead powder and 2 & alumina powder were at H50 vibrations per minute while changing Times between 1 and t hours vibrates

. ^{1 The} same ball mill was used for the ball mill wiping process, with 1OC balls made of stainless steel, 1/4 inch (12.7 cm) in diameter. The same powder batches (corresponding to a ratio of 1 a 1 each of the sample content of the balls and the puivera) and the same Vlbrationsgsechwindifclceit as for the ViDratioüBislsehung s & lt vary Jei: Hahldeuern swisohen -j and 8 hours

For day .uoautouri ^ I- · laugh .-, u \>. .: L ^11. *. ^v ieo / -aiaechlne asit nnoha ideietahlblät t * i '/ ·., a -; & ϊ% - ■■''"i> /.-. ϊ ■: ■■ .'-. ^ g« ri pea .minute in einta nohan Jxaebehaltär ixiiirtph, -.it · ■ ^.; ji _ _: ,, ilsipulver and 6 g clay rt »where Jit-.e ^ r. _S ;. ^ - J« r? ":;: ■« ■. · ■■. -Joi - ^: »was id ig, ia. The

he su ..i ·· άet: *. * ..,. uia ^ ü Ha-sci,.,; ^ · w ^ .-. lif tal each one his Lttufeeit ν & χΐΐ * ;. ά -töcaeisiia). ',' ir.-ii «! be i,;! - "äb" n, u * an ub # r ~ taä8ig "n oxidation of the BM" ipulv * i "5.η.ί ·;: ·: ί _ώ β ilbtrhltsung« uvoreukaaaea. L'i.e gestusfce Kiechsfit was criticized for 10 and 4 kinates.

PAD ORIGINAL S09881 / 0402

The mixed powders were all subjected to chemical reduction by means of caustic in order to eliminate most of the lead oxide originally present in the lead powder and the subsequent lead oxide produced by the mixing process. Experiments have shown that an extensive reduction in lead oxide is achieved when oxidized egg powder is exposed to a stream of purified, dry ice powder for 24 hours at about 30 ° C. Consequently, this treatment was applied to the powder mixtures.

The reduced powder mixtures were used in each case Chilled in hydrogen to skin temperature and then very quickly (to avoid reoxidation of the lead eu) in an extruder transferred, by means of which the subsequent deformation process was carried out·

A batch of approximately 100 grams of powder was required to pull the extruder. The powder was compacted and ejected in a single direct operation to produce 0.100 inch (2.5 µm) diameter wire. The strand prefi ratio was 40 ι 1, and no ohmization was used. The expulsion and the pressing was performed at a speed of 11 · "feet per minute (5.5 a / min) at room temperature, but the temperature of the dtrangpreßproduktee was about 60 ⁰ C, due to the strong deformation occurring ·

BAD ORKDiNAL.

909881/0402

A sample selection was analyzed ohtmlech, vub dl · quantity of the still existing Rettbitloxldt feu be · tinmen, please Analjrti Beige reed lead content of less than 1.0 fluted sprouts PbO and in general even less than 0.5 Gewienteproient PbO.

In the case of the Qtrcitcht produced in the blender betondera lead oxide Heetgehultt were found in the Of the order of 0.2% by weight and below.

Kit stranggeprelten the wires Zerreiflvereuohe were performed · The aut the mixed powders by Tlbration hergettellten wires showed a Ztrreieftttigktit Tan dtr order of 3900 lbe / in ² (274 kg / cm ^2). The Kugelntthlen-PuIvergemisehe were siemlloh stray bew. Etark different tensile strengths for the various Mahldausrs of mixtures but ι the measured strengths were all hufetr old 5UOO ib / in ² (351 kg / ca ²⁾ for powder, the x 1-during times of 3tunden or were more ground · you nfcrotkopisohe Under * the internal structure investigation dieter mother ceigte that obgl IOH some Tonerdtag ^ lomtrationen were anwetand, ditptrgitrt dtr greater part of the clay evenly and \ υ & fold 600 at magnification was sufficiently fine, partly aufgelöet " u will. For the powder mixtures from the MIe «haatchint, the pressed wires showed progressively larger flakes of flakes with lengthening kisoh sides between 15 and 40 minutes.

the ruptures: -Ji ^ iten of some 450 oils 5> i> 00 lb / inch

BAD OmiUAL 909881/04 02

(516 to 387 kg / oa) vary. Found ⁽²³⁸³ kg / ca) for wires Al · · Auenahm and inexplicably Wei ·· word "" in "ZerreiöfeetigJceit yon" tv * 5450 lb / inch, dl "au · d" m powder mixture .da · only during 10 Minutes after it was processed on the mixing machine, “Further tests are therefore required”, including whether the results are either “permanently reproducible” or only “in unimportant, abnormal Result su val iet

The ball grinding resulted from the three undertaken Mieohproeeeeen and since "high-speed lessons higher? n la the sin products · The inferiority of duroh vibration Pulrer (although the ·· imaer nooh «in harder ·· product usually lead) can bus) hawk on di · Tend · »· for the lead and alumina pulses · γ surUuUt be returned, see during the · Yibretioneaiechen · as a result · of ·· Dioht «und« re * hi * d · segregate. Zudea let da · Yibrationaeieohen a picture ·· Τ · γ-drive, τοη d ·· only slightly «aeohanisoh * 7omttAd« rung «n der Powder heights can be expected while considerable deformation and since · HinvinswiJigvn the alumina parts in db lead · part by that lugelyerahlen is caused. volume the high-speed mieohen «can also be expected, deJ dl · · • in · noteworthy change in shape due to · d ·· Aufeohlag · d * r «ioh e very fast rotating stirring blades on the · powder particles · »· calls. Clumps of clay τοη clay tend to be, through di ··· both pro ····· broken up su w «rd« n, obgl «ioh« in «g« like ·· fend «ns for dl

BATH ORIGINAL

909881/0402

· ¹⁰ · 153315b

Elektroatiaoher charges of the alumina parts ohen duroh Al · Anweeenhelt τοη aetalllaohea lead on «in Mlniaua b« aehränlrt is · Di ·· would b * i ά · χ Distribution of the same Anaätae or batches, In * - beaondere la Pail of the lugelaahlaaeohlne, ▼ your »metal container old get old dta Hoohtourtnrtthrtr old »an insulating 01a * · container, nut el i oh min.

Microacopy examinations tended to show that old kugelreraahl "n" n PulYergeaiaohen finer and more uniform diiperions were also obtained from the Htthraaeohln. further gave, although about equal Z «rr« iflf «atlglcalt« n iu received, die kugelYeraahlenen Oeaieohe la allgeaelnen beeoere Irgebnla ·· in the case of tendons aa final product, luflerdea results in "loh, if Also, more costly jobs are required to be expensive were, dech the Lotvendlgkelt, this gate ale a row interrupted xlnsoperationsea duro ears »dal kontlnuler · High overhaul required.

Sound of the three Miaohproaeeaen therefore aeheint daa lügelToraahlen 4 attractions. Applying theeea Proaeaaea were further Yereuch · durohleitt, among other things the effect -reraohleden higher Sealing proportions of clay in the pulp powder. Oealaohe old retained from 1.3 and 5 Toiuaenproaent alumina powder were during among others, their alumina content is rare, then reduced and under the same conditions as before atranggeprefit · The grinding times became progressively old dea clay » salary increased, among other things veriugiegen that an outer slaperalon of the Clay was removed and had taken place within the lead particles The extruded materials showed those in the following table given oharakterlatlaohen phyaiJcalieohen Blgeneohaften, the for The same aaweoke auoh the entapreohenden values for materials au · the same powder, each without reduction of the lead oxide · «

SAD ORIGINAL

- r r -

1 ToI * al ₂ 0y Reduced 20.1 19.1 3 ToI * Reduced 5 ToI * 1 ₂ 0 Reduced Ballwedding
2 hours 3.7 0.20 'Al ₂ O, I forgot the ball
5 hours ! fled
redu-
Beers 3420
3860
4310 Ball milling
4 hours 4360
4940
5500 not
redu
adorns 5230
6300
7070 Test voltage
(Ib / Zoll2) 5120 Hicht
redu-
slert 6340 7950 0.05 * elongation
0.1 * 350
4900 4560
5420
6150 ZerreiÄfeetig-
speed (lb / inch ^ 6030 4280
5080
5670 7080 * Stretching to
a mother 14th 7220 10 6th length 4 "V transverse 48 43 16 —— lsohnittsf lache ¹ 7th 1.8 2.2 <0.5 3.1 reduction
the transverse
• lack of water 20th 1 0 isiastlsltäta-
module (Young's
! Μ,) * lOoib / inch 2.1 3 22.0 2.6 20.3 Strand pree-
druok 2.2 0.52 0.44 (t / inch *)
at room temp. 30.9 Oxide content
in weight * PbO 27.9 12.5 8.1

Also below comparison were some samples of the powder, that did not contain any clay during various ball mills, e then undergo the same lead oxide reduction treatment as that ^ subject to and on it under the same conditions as "Torrfcehaaä itranggepreeet. The average tensile strengths obtained were given in the following table

Duration of the bullet
grinding in hours Tensile strength
lb / in ² 2 909881/04
3 3083
2 3583
3624
"3772
3793

BATH

The small changes in the tensile strength are in agreement with the changes in the residual dioxide content swisohsn the hats

Creepy tetras were used on mueters as a "material" that had been reduced and extruded according to the invention from an oemieoh of lead powder and 1% by weight of alumina ball-milled. The special material had a Zsrreiflfeetigkeit τοη 5900 Ib / to11 and an elongation of H *. Some of these Krieohtests were carried out at room temperature (20 ⁰ O), and others at 80 ⁰ C. For comparison gleiohe feete were to Muetern aue pure lead at room temperature durohgeftthrt · The tests were Spannungebruohtest · _f which consisted of a fixed voltage to a pattern in bucket specified temperature and determination of the time is applying "the necessary" was under this conditions a fraction of Lusters hsrbeisufuhr "The entire stretch" that had occurred "was also measured near the brush. The results are given in the following table "In <t" r a flux (♦) anseigt "that since the bruoh nooh had not occurred and the fsst nooh was continued"

909881/0402

I. Time bi sub Bruoh (in hours) 3 80 ⁰ C - Pb • - ■ - ■
Elongation (z) tension
(lb / inch ² ) Pb / 1 * Al ₂ O - 6th 20 ⁰ O (* especially on 4 Vq) 500 20 ⁰ C ** - 500 33 600 a » - 33 48 800 - - 3 48 2000 - 95004 40 minutes, 50 2500 - 2000 * - - 3000 5500 ♦ 20004- - 3500 5500 ♦ 20004 - - 3700 5500 ♦ 18th - 3900 - - 9 4000 - ■ - - 4300 5500 ♦ - 8th 4500 - - 6th 5000 1454 - 5 62

(Remark from the * German representative * ι (x) Zs engUecheη Text eteht 4 YXi where A true ο he inl I can mean "area" - area or transverse eohnlttef height. It was therefore anetelle ron A (area) Q f Quaraohnltjj ft «FlMohe) a ^ eeetet. In the table on 8. 8 the original printout% / k has been replaced with 4 Y transverse center surface)

BATH ORIGINAL

9098B1 / 04Ö2

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In addition to the high tensile strength and reliability of the inventively manufactured materials alt a «relatively high ratio of test voltage to tensile strength, “These materials also have a lower level of heat »To inflate your legs, because only small amounts of thatch of lead oxide and associated bsw. associated lead carbonate are present. This is shown in the following table

Goods handling Density in g / om * Fb / al ₂ O ₃ (f *) about 1 hour tea temperature ⁰ C • 10.7 • 10.7 Pb / Pbo (Ji) Room temperature (2O ⁰ C) 10.7 11.1 55 10.7 • 11.1 100 10.7 11.1 150 10.4 11.1 200 10.2 11. · 250 9.5 300 8.0

The strength of the tightly pressed lead oxide-reinforced lead drops noticeably as soon as the 3-tier reserve temperature is increased and swar as a result of the grain size of the lead oxide components, which by Deformation is caused at higher temperatures. In the case of clay, which is already available in finely divided form, the absence of

909881/0402

BATH ORIGINAL

COPY

belt the iePhlmmena to the right strand free meter tapes, the ohae, significant loss of strength in the Sndprodtüct applied can be.

This is evidenced by the Versuoha results presented in the The following table for alumina-hardened lead (Fb / algO) in Terglelah old lead oxide Yerstarkea lead can be given (Fb / PbO). the related contents of hardening, dispersed substances at 3 volume percent alumina and 7 »5 volume percent lead oxide. 9 ·· Relatively high lead oxide ratio explains the higher strengths, obtained at the two lowest compression temperatures.

Extrusion S trangpres sdruok
t / inch ² Tensile strength
lb / 2oll ² 6900 Riser temperature 21 6200 100 16 6100 5000 170 14th 5900 4300 240 9 δ 300 3300 310
• 4200

In addition to creating a process iur manufacturing you The period of the hard lead soles the present invention as well Process for the production of a commercial bsw, yerauf »productsβ in

909881/0402

BATHROOM 0RK3INAL

COPY

•• intη area tin, ntal ion «in lead powder mixture, dft · eut fabrication of dispersed hardened lead duroh extrusion odtt other Deformation presses are suitable for which an ohemieohe reduction precedes, with the · ··· powder here te longitudinal process in the Ml- • ohen Clay lead powder and a ceramic oxide in an oxidizing Atmosphere, preferably in a KugelmUhlenvorriohtung, exists and an intimate mixture of the ceramic oxide powder dispersed through the lead powder with the lead parts, whereby dl · BIeiteHohen are overcharged with lead oxide, produces · B · is See below »that there · · ο manufactured powders» that · reasonably stable is ι can be held over “rhebllohe storage time before ·· for the production of dispersion hardened, for example lead duroh ohemieohe Reduction and subsequent shaping is set.

The invention also relates to lead powder made from lead oxide with a lower proportion of ceramic-free oxide powders, finely dispersed therein, and in a preventive amount, 0.1 and 10 volumes per volume with the least A substantial proportion of the ceramic-free oxide layers, embedded in the Bleltellcheti * and also diaperslonsgehirttt lead, consisting of a lead matrix with a substantially ml% dispersion of submicron clay particles as the H for the Dlaptreicuehärtung, and a leaf loxiary; f content of less than 1 (towiohtsprosen »PbO, preventive growths are more than 0.5 owluhtsprossnt, whereby the clay bulbs are prefectively swl ^ ohtn C _f 1 and 10 volumes present inoluair *.

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9098 ν 1/04 C 2

BATH ORIGINAL

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Pmtentaneprtlohe BATH ORIGINAL

900881/0402

Claims (1)

Claims ο to oo 1. Procedure on Henttllun "from the" p "BÄ.OTHf" härtettm Bltl, thereby ft kenne · wages, 4 ·· · ■ t> «eteh * au · the process« nietuf # n de · Innigen Wieohtn · τοη BlelpulTer and a · »kl« lntrta share • in ·· kcrftBlrtntn 0xidpulr «r · la» in · »oxidizing ataoephera«, dl · dl · lead parts al "lead oxide overlooks and here dl" To * aaa «nb * llung dl" Mr TeHohen prevented by Druokrereohwlllung , while · 1η · la * ··· ηΐ11οη · η glelohfttralg «dispersion of the ksraalsohen oxide is obtained, the subjection of this Oenlsoes a reduction in episodes on the basis of a reduction in the main size of lead oxide / vorranglioh In Hlnsioht on carrionic oxide because of the greater stability of the latter "and subjection of the eo reduced Pulverge also a »Terforaungsproaess» among other things Lead parts in a susaaaeanän.rende matrix old dea everywhere darla pearled ceramic-based oxide su naal ^ anleren ^. 2 · Method according to claim 1, fladuroh gekennselohnet, since · the ο Reduction process consists in using the powder mixture of a Teapera ο door of about 3004C in aa Stroa of Trookenea Hydrogen wKlustti about 24 hours less than 1 Oewlohteaneaent PbO su erreleben, _ßÄn - ■ -., .., ..... ' 5 «Procedure naoh tin ·· dtr previous aneprtiohe, dft · by gekennaelohnet, dftf dtr Ytrforaungsprostss la Strangpreaetn dte rtdualtrttn Pulvtrgtaisohts btattht. 4 Process star Her tt β llung tint Bltlpulrtrgtaleohts, Aft * for dlt fabrication tob ditpenienagthfirtette Bltl duroh the following ohtaisehs reduction, followed τοη tinea deformation - proatβa getlgntt let «daiuroh gtktnnatlohnet, dal ta aua dta Mix τοη lead powder and tlnta pulverformigeη keraeiechen oxide in an oxidizing Ataoaph & rt beeteht, un tin intimately ·· Otalaoh dta ceramic oxide powder »diapered through daa bltipulrtr back» through, old dtn old lead oxide oversized lead powder tilohen htraitatelltn. 5 · Procedure naoh tlnta dtr rorhergthendtn inaprUoht, dadureh gekenneeiob.net, that Tontrdt (Al ₂ O-) ala ktraaleohtt oxide is used. 6. The method according to claim 5 · thereby ftktnneelanntt, dft! Alumina powder τοη Eubaikroner part size and lead powder old an approximately 100 times larger part size Terwendei; will" 7. Method according to claim 5 »in that Bltl powder with a nominal particle size τοη 300 Maaohtn (more than 53 microns) and alumina powder ait a noaintlltn TtIlbhtngrt3? used in the range of 0.030 to 0.005 microns 909881 / 0A02 BATH ίο β. Method aaoh · 1μι dor rorherfahren ABaprttehe, daduroh 4 ·· kenaie is worthwhile, since · oxygen al · oxldUroado Ataoaphar · is used. 9. Yorfahron naoh oIbm dtr Yorhergohondoa An ^ rttoht, f «k« niiMlohB «t, dal dl · Mlaehituft Ib dor foaolaeaaott do · Bloipulvoro and doo keraeliohon Oxldynlvore boet * h%. 10. Pulrergeaieoh door Heretellung tob dleper "lenogehärt" tea Blol duroh oheaisohe leduktion and naohfolgeade Yerforaunf de · · FuIrer, daduroh gekennaelohnet, Ab · oo a * among others old lead oxide MehUlltoa BIeipulrerto High old one "smaller proportion of keraal- • o ^v:" B Oxidpulrertellehen beeteth, dlo long in it diaporglerfe • lad, old wenlgetene a · «weoentllohen part aa keraeieohoa OxldtollohOB» AIo la the Bleltollohen embedded. , 11 «Pulvergeaieoh naoh Aavpruoh 10» Aaduroh gokenaselohaot, AIo koraaloohoB Oxidtellohen foaordotolloaoa tob • ind. 12 · Dlepereiona «ehirtetee lead, konn« oleiu »t« «raw olM Blol- • atrlK «Lt a la weeentliohen fleiohf« mature WeperoioB tob • ubalkrOBOB Tonerdetellohen al · prlnelpielle · dlep «r * loBOht>« «B-de · Mean UBd an · anodized content tob less than I protent FbO 909881 / CU02 bad original