mishraatu

ispaat ek mishradhaatu hai

do ya adhik dhaatvik tatvon ke aanshik ya poorn thos-vilyan ko mishraatu ya mishr dhaatu (Alloy) kehte hain. ispaat ek mishr dhaatu hai. praay: mishr dhaatuon ke gun us mishradhaatu ko banaane vaale sanghatakon ke gunon se bhinn hote hain. ispaat, lohe ki apeksha adhik majaboot hota hai. kaaainsa, peetal, taaainka (soldar) aadi mishraatu hain.

anukram

parichay

peetal ka deepak

mishradhaatu (Alloy) vyaapak roop mein ek aisa shabd hai jiska prayog kisi bhi dhaatvik vastu ke liye hota hai, basharte vah raasaayanik tatv na ho. mishradhaatu banaane ki kala ati praacheen hai. satya to yeh hai ki kaaainse ka mahatva ek yug mein itna adhik tha ki maanav sabhyata ke vikaas ke us yug ka naam hi 'kaansya yug' pad gaya hai. yadyapi shuddh dhaatuon ke kai upayogi gun hain, jaise ooshma aur vidyut‌ ki suchaalakata, tathaapi yaantrik aur nirmaan sambandhi kaaryon mein saadhaaranataya shuddh dhaatueain upayog mein naheen laai jaateen, kyonki inmein aavashyak majabooti naheen hoti. dhaatu ko adhik majaboot banaane ki sabse mahatvapoorn vidhi dhaatumishran (alloying) hai. is disha mein 19veen shataabdi mein bahut adhik prayaas hua, usi ka fal hai ki anek upayogi kaaryon ke liye aaj paaainch hajaar se bhi adhik mishradhaatueain upalabdh hain aur nai mishradhaatueain taiyaar karne ke liye nitya nae nae prayog kiye ja rahe hain. aaj kisi vishesh upayog ke liye ichhit gunonvaali mishradhaatueain banaai jaati hai.

dhaatueain jab kisi saamaanya vilyan, jaise aml, mein ghulati hai tab ve apne dhaatvik gunon ko chhod deti hain aur saadhaaranataya lavan banaati hain, kintu pighlaane par jab ve paraspar ghulati hain tab ve apne dhaatvik gunon ke sahit rahati hain. dhaatuon ke aise thos vilyan ko mishradhaatu kehte hain. anek mishradhaatuon mein adhaatueain bhi alp maatra mein hoti hain, kintu sampoorn ka gun dhaatvik rahata hai. at: 1939 i0 mein amareeka vastu pareekshak parishd ne mishradhaatu ki nimnalikhit paribhaasha ki-

mishradhaatu vah vastu hai jismein dhaatu ke sab gun hote hain. ismein do ya do se adhik dhaatueain, ya dhaatu aur adhaatu hoti hai, jo pighli hui dasha mein ek doosare se poorn roop se ghuli rahati hain aur thos hone par spasht paraton mein alag naheen hoti."

praarambh mein mishradhaatu ka adhiktam upayog sikkon aur aabhooshanon ke banaane mein hota tha. taaainbe ke sikkon mein taaainba, tin aur jasta kramash: 95/4 tatha 1 pratishat rahate hain. san‌ 1920 tak England mein chaaaindi ke sikke, 'starling' chaaaindi ke banaae jaate the, jismein chaaaindi aur taaainba kramash: 92.5 aur 7.5 pratishat hote the. amareeka mein chaaaindi ke sabhi sikkon mein chaaaindi aur taaainba kramash: 90 tatha 10 pratishat hote hain. England ke sone ke sikkein mein sona aur taaainba kramash: 91.67 aur 8.33 pratishat hote hain aur amareeka ke sone ke sikkon mein sona 90 pratishat tatha shesh anya dhaatueain, visheshakar taaainba rahata hai. plaitinyam, sona tatha chaaaindi ke aabhooshanon ke rango mein sundarata laane ke liye unako kathor, majaboot tatha tikaaoo banaane ke liye, ya unhein saste moolyon mein vikraya ke liye doosari dhaatuon ke saath milaakar kaam mein laate hain.

yeh nishchaya karna ki mishradhaatueain saadhaaran mishran hain ya raasaayanik yaugik, ek jatil samasya hai. kuchh arthon mein ye raasaayanik yaugik hain, kyonki jab sodiym saras banaaya jaata hai, tab sodiym ke har ek tukade ko paar mein daalne se prakaash ki teevr jvaala niklati hai aur paara garam ho jaata hai, yeh yaugik banane ka lakshan hai. isi prakaar pighlate hue sone mein jab ailyuminiym dhaatu ka ek tukada daalte hain, tab itni adhik ooshma utpann hoti hai ki sampoorn pighli hui dhaatu ujjaval prakaashamaya ho jaati hai. anek mishr dhaatuon ka rang apne avayav dhaatuon ke rangon se bilkul bhinn hota hai. udaaharanaarth, chaaaindi aur jasta dona shvet rang ke hote hain, kintu inse jo mishradhaatu banti hai usaka rang ati sundar gulaabi hota hai. sona peela aur ailyumeeniym shvet hota hai, kintu inki mishradhaatu ka rang ati chamakeela neelalohit hota hai. yeh gun bhi yaugikon ka hai.

mishradhaatuon ke galanaank nikaalne par gyaat hua hai ki mishr dhaatuon ka vyavahaar do prakaar ka hai: kuchh mishradhaatuon ka galanaank jaise jaise kisi avayav dhaatu ki maatra badalti hain vaise-vaise badalta hai, yeh mishran ka gun hai aur kuchh mishradhaatuon ka galanaank ek sthir taap hota hai, jo prakat karta hai ki mishradhaatueain yaugik hain.

mishradhaatuon ke bhautik tatha raasaayanik gun apni avayav dhaatuon ke gunon se bhinn hote hain aur mishradhaatuon ke gun kisi bhi prakaar se avayav dhaatuon ke gunon ke maadhya naheen hote. yeh bhinnata is kaaran se hai ki jab dhaatuon ko ek saath pighlaate hain, tab ve kitne hi antaraadhaatuk yaugik tatha thos vilyan banaati hain. mishradhaatu ka ghanatv apni avayav-dhaatuon ke maadhya ghanatv se kam ya adhik ho sakta hai. kuchh mishradhaatuon ka rang apni avayav dhaatuon ke rangon se bilkul hi bhinn hota hai. ye apni avayav dhaatuon se kathoratar, kintu kam lacheeli tatha ghaatavarghya aur adhik bhangur hoti hain. mishradhaatuon ka galanaank sarvada adhiktam taap par pighlanevaali avayavadhaatu ke galanaank se bhi kam hota hai. aur praaya: nyoonatam taap par pighlanevaali avayav dhaatu ke galanaank se bhi kam hota hai. udaaharanaarth, ek mishradhaatu, jismein seesa (4 bhaag), tin (2 bhaag), bismath (6 bhaag) tatha kaidamiym (1 bhaag) hain, 75˚asein0 par galati hai, jab ki nyoonatam taap par pighlane waali avayav-dhaatu, tin ka galanaank 232˚ sein0 hai. ye sab ve gun hain jinke kaaran mishradhaatueain shuddh dhaatuon se adhik moolyavaan ho jaati hain tatha udyog mein adhik upayogi siddh hoti hain.

vargeekaran

oopar varnit falon dvaara tatha sookshmadarshi, ex-kiran varnakram maapi, ooshmeeya tatha raasaayanik vishleshan aur doosare bhautik pareekshanon dvaara mishradhaataon ke sangathan tatha kristaleeya rachana ke vistrut adhyayan ke parinaamasvaroop, mishradhaatuon ko teen shreniyon mein rakha gaya hai. yeh vibhaajan mishradhaatuon mein avayav dhaatuon ke paramaanuon ka samooh kis prakaar se sangathit hai, uske aadhaar par kiya gaya hai. ye teen shreniyaaain nimnalikhit hain:

samaanya mishran

Alliage precipite.png

is prakaar ki mishradhaatuon mein avayav dhaatueain jab pighli hui hoti hain, tab ve ek doosare mein ghuli hui rahati hain, kintu thos hone par dhaatuon ke kristal alag-alag ho jaate hain, arthaat‌ dhaatueain paraspar avileya hain. is prakaar mishradhaatu pratyek avayav dhaatu ke shuddh kristal ka mishran hoti hai aur thanda karne par koi ek avayav dhaatu thos roop mein pruthak‌ ho jaati hai. udaaharanaarth, ek taral mishradhaatu, jismein maatraanusaar 10 bhaag seesa aur 90 bhaag tin hote hain, jab thandi ki jaati hai tab shuddh tin ke kristal pratham usi prakaar se pruthak‌ hote hain jis prakaar shuddh him ke kristal cheeni ke tanu vilyan mein se thanda karne par pruthak‌ hote hain. jis taap par tin ke kristal pruthak hona praarambh karte hai, vah taap shuddh tin ke galanaank se kam hota hai. tin ke galanaank ko jab usamein seesa ghula rahata hai, gyaat kar seese ka anubhaar usi niyam dvaara nikaalate hain jis niyam se paani mein ghuli vastaon ka anubhaar nikaalate hain. is vidhi se un kai dhaatuon ka anubhaar nikaala gaya hai, jo tanughaatvik vilyan mein alag parmaanu ke roop mein rahati hai. seesa-ainteemani mishradhaatu mishran shreni ki hai. ainteemani bhangur hota hai aur seesa mulaayam. mudran dhaatu CC, ainteemani aur atyant kam maatra mein tin ki mishradhaatu hai. is mishradhaatu mein ainteemani ki kathorata to hoti hai, kintu yeh usaki tarah bhangur naheen hoti.

thos vilyan

is prakaar ki mishradhaatuon mein ek avayav dhaatu ke parmaanu doosari avayav dhaatu ke kristaleeya dhaaainche (crystalline lattice) mein bhali-bhaaainti baith jaate hain. thos vilyan shreni ki mishradhaatueain do bhinn prakaar ki hoti hai:

Alliage solution solide.png

  • (k) antaraakaashi (interstitial) madhya thos vilyan-is prakaar ki mishradhaatuon mein adhaatu tattv, jaise haaidrojan, kaarban, naaitrojan aur boraun ke laghu parmaanu dhaatu ke kristaleeya dhaaainche ke madhyasthaanon mein apna sthaan banaate hain. saadhaaranat: isse dhaatu ki rachana mein koi vishesh antar naheen padta hai, keval usamein thodi si vikruti (distortion) aa jaati hai. haug (Hogg) ke anusaar antaraakaashi madhya thos vilyan tabhi baneinge, jab adhaatu aur dhaatu ke paramaanuon ke arddhavyaason ka anupaat 0.59 se kam ho.
  • (kh) pratisthaapit thos vilyan ve hote hain, jinmein ek tatv ke parmaanu doosare tatv ke kristaleeya dhaaainche mein unheen sthaanon ko grahan karte hain jahaaain par unke pehle doosare tatv ke parmaanu sthit the. is prakaar ki thos vileyata donon tatvon ke paramaanuon ke arddhavyaas sarvasam (identical), ya lagbhag samaan hon, to thos vileyata poorn roop se hogi. udaaharanaarth, taaainbe ke parmaanu ka arddhavyaas 12.75 nainomeetar tatha nikal ke parmaanu ka arddhavyaas 12.43 nainomeetar ka hota hai, at: inki mishradhaatu mein thos vileyata poorn roop se hogi. agar arddhavyaason mein adhik antar ho, jaise tin aur seese ke paramaanuon ka arddhavyaas kramash: 15.0 nainomeetar tatha 17.46 nainomeetar hai, to keval seemit thos vileyata hogi. agar donon dhaatuon ke rinavidyuti antar (electronegative difference) mein kami ho, to is prakaar ki thos vileyata aur bhi achhi tarah se hogi.

Alliage ordonne desordonne.png

taaainba-nikal ki anek mishradhaatueain jinka mahatvapoorn upayog hai, thos vilyan ki shreni mein aati hain. udaaharanaarth, ve mishradhaatueain jinse nikal ke sikke, rifle ki goliyon ki topiyaaain aur ek taar jiska vaidyut pratirodh adhik hota hai, banta hai. Canada ke bahut se khanijon mein taaainba aur nikal ke salfaaid hote hain, jinko galaane se ek mishradhaatu milti hai. ismein nikal aur taaainba kramash: 67 aur 28 pratishat tatha shesh paaainch pratishat mein loha aur mainganeej hote hain. is mishradhaatu ko monel (Monel) dhaatu kehte hain. yeh adhik tanya, lacheeli tatha sankshaaran pratirodhak hoti hai.

antaraadhaatuk yaugik (Intermetallic compound)

saadhaaranat: dhaatueain ek doosare ke saath sanyog kar yaugik naheen banaateen, kintu ooshma vishleshan dvaara gyaat hua hai ki dhaatueain ek doosare ke saath sanyog kar bahut adhik sankhya mein yaugik banaati hain. in yaugikon ka vargeeya naam antaraadhaatuk yaugik hai. is prakaar ke sabse adhik yaugik kshaar aur kshaareeya mitti ki dhaatueain, aavart saarani ke visham upavargo (odd subgroups) ki dhaatuon ke saath sanyog karke, banaati hain. in yaugikon mein dhaatueain kis maatra mein mili hui hain, isko raasaayanik sootron dvaara darshaate hain. in sootron ke adhyayan se gyaat hota hai ki is prakaar ke yaugik sanyojakata ke un sab niyamon ka ullanghan karte hain jo dhaatu tatha adhaatu ke sanyog se bananevaale yaugikon dvaara pratipaadit hue hai. udaaharanaarth, sodiym, tin aur seesa ke saath raasaayanik kriya kar nimnalikhit yaugik banaata hai :

NaSn6, NaSn4, NaSn3, NaSn2, (NaSn), (Na4 Sn2),
(Na Pb5), (Na4 Pb9), (Na Pb), (Na2 Pb), tatha (Na4 Pb).

anek antaraadhaatuk yaugik bahut sthaayi hote hain aur apne galanaank se adhik taap par garam karne se bhi apni avayav dhaatuon mein vightit naheen hote. ye yaugik taral amoniya mein ghulate hain aur is prakaar se jo vilyan taiyaar hota hai, vah vaidyut‌ chaalak hota hai. jab inka vaidyut apaghatan kiya jaata hai, tab ek avayav dhaatu, jo doosari ki apeksha nyoon dhanavidyuti (electropositive) hoti hai, dhanaagr par jamati hai aur doosari rinaagr par. antaraadhaatuk yaugik kyon banaata hai, iski abhi tak saiddhaantik vyaakhya naheen hui. keval itna hi pratipaadit ho paaya hai ki ve dhaatueain, jinke gun ek se hain, ek doosare ke saath sanyog naheen karti hain. chooainki is prakaar ki mishradhaatueain kathor, bhangur, bahut hi kam tanyasheel tatha lacheeli hoti hain, at: inmein se keval kuchh hi upayogi hain.

pramukh mishradhaatueain

sab mishradhaatuon ko saadhaaranataya lauh tatha alauh mishradhaatuon mein vibhaajit kiya gaya hai. jab mishradhaatu mein loha aadhaar dhaatu rahata hai, tab vah lauh tatha jab aadhaar dhaatu koi anya dhaatu hoti hai, tab vah alauh mishradhaatu kahalaati hai.

alauh mishradhaatueain

kuchh mukhya alauh mishradhaatueain nimnalikhit hain:

(1) ailyuminiym-peetal (Aluminimum-brass) - iske sangathan mein taaainba, jasta aur ailyuminiym hain, jo kramash: 71-55, 26-42 tatha 1-6 pratishat tak hote hain. iska upayog paani ke jahaajon tatha vaayuyaan ke nodakon (propeller) ke nirmaan mein hota hai.

(2) ailyuminiym-kaansa - ismein taaainba 99-89 tatha ailyuminiym 1-11 pratishat tak hota hai. yeh ati kathor tatha sankshaaran avarodhak hota hai. iske baratan banaae jaate hain.

(3) babit (Babit) dhaatu - ismein tin, ainteemani tatha taaainba ki pratishat maatra kramash: 89, 7.3 tatha 3.7 hoti hai. iska mukhya upayog baul biyring banaane mein hota hai.

(4) ghanta ghaatu (Bell metal) - ismein taaainba aur tin ki pratishat maatra kramash: 75-80 aur 25-20 tak hoti hai. isse ghante aadi banaae jaate hain.

(5) peetal - ismein taaainba 73-66 tatha jasta 27-34 pratishat tak hota hai. iska upayog chaadar, nali tatha baratan banaane mein hota hai.

(6) kaarbolaaya (Carboloy) - yeh tangstan kaarbaaid tatha kobalt ki mishradhaatu hai. isse ragadne aur kaatne vaale yantr banaae jaate hain.

(7) kaunstainten (Constantan) - ismein taanba 60-45, nikal 40-55, maiganeej 0-1.4, kaarban 0.1 pratishat tatha shesh loha hota hai. iska upayog vaidyut-taapamaapak yantron tatha taap vaidyut-yugm (thermocouple) banaane mein hota hai, kyonki yeh vidyut‌ ka prabal pratirodhak hota hai.

(8) delta dhaatu (Delta metal) - ismein taaainba 56-54, jasta 40-44, loha 0.9-1.3, mainganeej 0.8-1.4 aur seesa 0.4-1.8 pratishat tak hota hai. yeh mrudu ispaat ke samaan majaboot hai, kintu usaki tarah saralata se jang khaakar nasht naheen hoti. iska upayog paani ke jahaaj banaane mein hota hai.

(9) do dhaatu (Dow metal) - ismein maigneeshiym 90-96, ailyuminiym 10-4 pratishat tak tatha kuchh anshon mein mainganeej hota hai. iska upayog motor tatha vaayuyaan ke kuchh hisson ko banaane mein hota hai.

(10) jarman silvar - ismein taaainba 55, jasta 25 aur nikal 20 pratishat hota hai. kuchh vastuon ko banaane mein chaaaindi ke sthaan par iska upayog karte hain, kyonki isse bani vastueain chaaaindi ke samaan hi hoti hain.

(11) harit svarn (Green gold) - ismein sona, chaaaindi aur kaidamiym, kramash: 75, 11-25 tatha 13-0 pratishat tak, hote hain. iske aabhooshan banaae jaate hain.

(12) gan metal (Gun metal) - ismein taaainba 95-71, tin 0-11, seesa 0.-13, jasta 0-5 tatha loha 0-1.4 pratishat tak hota hai. isse batan, bille, thaaliyaaain tatha daaainteedaar chakr (gear) banaae jaate hain.

(13) maigneliym (Magnalium) - ismein ailyuminiym 95-70 pratishat tatha maigneeshiym 5-30 pratishat tak hota hai. yeh mishradhaatu halki hoti hai. iska upayog vigyaan sambandhi yantron tatha tulaadand banaane mein hota hai.

(14) naaikrom (Nichrome) - ismein nikal 80-54, kromiym 10-22, loha 4.8-27 pratishat tak hote hain. ooainche taap par iska sankshaaran naheen hota tatha iska vaidyut pratirodh adhik hota hai. iska upayog ooshmak (heater) banaane mein hota hai.

(15) paalau (Palau) - ismein sona 80 tatha pailediym 20 pratishat hote hain. moosha (crucibles) aur thaali banaane mein plaitinm ke sthaan par iska upayog kiya jaata hai.

(16) parmalauya (Permalloy) - ismein nikal 78, loha 21, kobalt 0.4 pratishat tatha shesh maiganeej, taaainba, kaarban, gandhak aur sileekan hote hain. isse telephone ke taar banaae jaate hain.

(17) soldar (Solder) - ismein seesa 97 tatha tin 33 pratishat hote hain. yeh dhaatu do dhaatuon ko aapas mein jodne ke kaam aati hai.

(18) shot dhaatu (Shot metal) - ismein seesa 99 tatha aarsenik 1 pratishat hota hai. isse bandook ki geeli tatha chharein banaae jaate hain.

(19) tin ki panni (Tin foil) - ismein tin 88, seesa 8, taaainba 4 aur aintimni 0.5 pratishat hote hain. yeh panni cigarette aur khaadya vastuon ko surakshit rakhane ke liye unke oopar lapeti jaati hai.

(20) ud ki dhaatu (Wood metal) - yeh mishradhaatu sarvapratham ud ne banaai thi. ismein bismath 50, seesa 25, tin 13 aur kaidamiym 13 pratishat hote hain. iska galanaank bahut kam hota hai. aag ko paani chhidk kar bujhaanevaale, svachaalit yantron mein, jo plag (plug) laga rahata hai vah is mishradhaatu ka bana hota hai.

loh mishradhaatueain

aadhunik yug mein lauhamishr dhaatuon ka adhiktam mahatva hai. iske antargat ispaat aur dhalavaaain loha (cast iron) tatha pitvaaain loha (wrought iron) loha aate hain. jab shuddh galit lohe ko thanda karte hain, tab 1,535˚ sein0 par taral lohe se kristaleeya roop mein is prakaar ka loha niklata hai. isko delta loha (δ-loha) kehte hain. yeh loha doosare prakaar ke kristal mein 1,404˚ sein par parivrtit ho jaata hai. isko gaama loha (γ-loha) kehte hain. yeh 900˚asein0 ke oopar sthaayi rahata hai aur is taap par ailfa loha mein parivrtit ho jaata hai, jo saadhaaran taap par sthaayi rahata hai. loha aur kaarban ka ek yaugik banta hai, jismein kaarban ki pratishat maatra 6.67 hoti hai. is mishradhaatu ko semeintaait (Sementite) kehte hain. yeh mishradhaatu gaama loha (y-loha) ke saath thos vilyan banaati hai, jisko ostenaait (Austenite) kehte hain. ispaat mein kaarban ki maatra 0.5 se lekar 1.5 pratishat tak rahati hai. jab galit ispaat thos hota hai, tab ostenaait ke thos vilyan-kristal praapt hote hain. ye kristal mulaayam hote hain aur inse chaddare, chhad tatha taar saralata se banaae jaate hain.

motor gaadiyon ke vikaas ke saath saath ve tatv, jinko keval rasaayanajnya hi jaante the, ispaat ke saath mishradhaatu banaane ke upayog mein laae gaye. ye ispaat mishradhaatueain motor gaadiyon ke injinon ke hisse banaane tatha ye hisse jin yantron se banaae jaate hain, unako banaane mein kaam aati hain. udaaharanaarth, mainganeej se ispaat ki majabooti badhti hai aur yeh okseejan aur gandhak ko, jo ispaat ko durbal tatha bhangur bana dete hain, ispaat mein se alag kar deta hai. nikal ispaat ki majabooti ko bina usaki bhangurata badhaae badha deta hai. kromiym ki kam maatra ispaat ko kathorata pradaan karti hai aur iski adhik maatra ispaat ko sankshaaran se bachaati hai. stenales steel mein kromiym hota hai. vainediym-ispaat (vanadium-steel) aaghaatasah (shock proof) hota hai aur molibdenam‌-ispaat (molybdenum-steel) adhik kathor tatha ooshma avarodhak hota hai. ispaat-mishradhaatueain keval kaarban-ispaat se adhik mahaingi padti hain.

mahatvapoorn mishrit dhaatueain evam unke sanghatak

mishrit dhaatu —a—a—– sanghatak

1. peetal - taanba (75 pratishat) + jasta (25 pratishat)

2. ghanta dhaatu (Bell metal) - taanba (75 pratishat) + tin (25 pratishat)

3. kaansa - taanba (75 pratishat) + tin (25 pratishat)

4. jarman silver - taanba (50 pratishat) + jasta (25 pratishat) + nikel (25 pratishat)

5. elyumeeniym kaansa- taanba (50 pratishat) elyumeeniym (40 pratishat) + loha (10 pratishat)

6. gan metal - taanba (88 pratishat) + jasta (2 pratishat) + tin (10 pratishat)

7. type (priting) metal led (60 pratishat) + enteemani (30 pratishat) + tin (10 pratishat)

8. stenales steel - loha + kromiym + nikel

9. hindaaliym - elyumeeniym (91 pratishat) + maigneeshiym (9 pratishat)

10. delta dhaatu - taanba (55 pratishat) + jasta (41 pratishat) + loha (4 pratishat)

11. dach metal - taanba (80 pratishat) + jasta (20 pratishat)

12. monal dhaatu - taanba (27 pratishat) + nikil (70 pratishat) + loha (3 pratishat)

13. taanka (solder) - tin (67 pratishat) + seesa (33 pratishat)

14. bud‌aas dhaatu - bismath (33.5 pratishat) + seesa (33 pratishat) + tin (19 pratishat) + kaidamiym (14.5 pratishat)

15. kaanstaitan - taanba (60 pratishat) + nikil (40 pratishat)

16. mut‌aaj dhaatu - taanba (60 pratishat) + jasta (40 pratishat)

inhein bhi dekhein

  • mishr dhaatuon ki soochi

baahari kadiyaaain