stenales steel

is lekh mein sandarbh ya sootr naheen diye gaye hain. krupaya vishvasaneeya sootron ke sandarbh jodkar is lekh mein sudhaar karein. bina sootron ki saamagri ko hataaya ja sakta hai. (June 2015)

bejng faulaad (stenales steel) ek ispaat hai jo vaayumandal tatha kaarbanik aur akaarbanik amlon se kalushit (kharaab) naheen hota hai. saadhaaran ispaat ki apeksha ye adhik taap bhi sah sakte hain. ispaat mein ye gun kromiym milaane se utpann hote hain. ismein 15-20% kromiym, 8-10% nikel tatha saadhaaran steel hota hai. kromiym ispaat ke baahya tal ko nishkriya bana deta hai. pratirodhi shakti ki vruddhi ke liye ismein nikal bhi milaaya jaata hai. nikal ke sthaan par anshat: ya poornat: mainganeej ka bhi upayog kiya jaata hai. akalush ispaat ke nirmaan mein lohe mein kabhi-kabhi taamr, kobaalt, taaiteniym, niyobiym, taintaaliym, kolanbiym, gandhak aur naaitrojan bhi milaaya jaata hai. inki sahaayata se vibhinn raasaayanik, yaantrik aur bhautik gunon ke akalush ispaat banaae ja sakte hain.

san 1872 E. mein Woods aur Clark ne logon ka dhyaan is or aakarshit kiya ki lauh aur kromiym ki kuchh mishr dhaatuon mein na to jang (muracha) lagta hai aur na aml ke prabhaav se un par koi vikaar hota hain. peris mein aayaajit san 1900 E. ki pradashani mein ispaat ke kuchh namoone the jinki sanrachana aadhunik akalush ispaat ke samaan thi. san 1903 E. mein lauh, kromiym aur nikal ki mishr dhaatuon ko England mein peteint karaaya gaya. in mishr dhaatuon mein kromiym ki maatra 24 se 57 pratishat aur nikal ki maatra 5 se 60 pratishat tak thi. sanyukt raajya amareeka mein nikal aur ferokrom (arthaat kromiym-mishrit lohe) ko moosha (ghariye) mein pighlaakar tharmokapal banaane yogya ispaat ki rachana ki gayi. san 1905 E. mein lauh mein nikal, kromiym aur kobaalt ki mishr dhaatu se motarakaaron ke spaark plagon mein chingaari denevaale taar banaae gaye. san 1910 E. mein uchchataapamaapi nalikaaon ke liye Germany ne ispaat, kromiym aur nikal ki mishradhaatu ka aur san 1912 E. ke lagbhag England ne bandook ki naal banaane ke liye kromiym aur ispaat ki mishradhaatu ka upayog kiya aur chaakoo, chhuri aadi banaane ke liye ise peteint karaaya. baad mein keval nikal ya nikal aur kromiym ko ispaat mein milaakar banaai gayi mishr dhaatuon ke vibhinn mishran sanyukt raajya amareeka, England aur Germany mein peteint karaae gaye. in praarambhik mishranon ke aadhaar par ailyoomeeniym, seleeniym, maalibdeenam, silikn, taamr, gandhak, tangstan aur kolanbiym ko kromiym aur kromiym ispaat mein milaakar shreshth gunadharmavaale akalush ispaat banaane ke aavishkaar hue. Germany mein nikal ka abhaav hone ke kaaran san 1935 E. mein ek aise prakaar ke akalush ispaat ka nirmaan hua jismein nikal ke sthaan par mainganeej ka prayog kiya gaya aur mishr dhaatu banaane ke liye sahaayak ke roop mein naaitrojan prayukt hua.

kshayarodhak aur taaparodhak aadhunik akalush ispaaton ko paaainch vargon mein vibhaajit kiya ja sakta hai:

(1) jinmein kromiym ka upayog mukhya dhaatu-mishranakaari ke roop mein kiya gaya ho.

(2) jinmein kromiym aur ispaat ki mishr dhaatu ke gunon mein parivartan ke liye paryaapt maatra mein ailyoomeeniym, taamr, molibdeenam, gandhak, silikn, seleeniym ya tangstan ka upayog kiya gaya ho.

(3) jinmein kromiym, nikal aur ispaat ke mishranon mein poorvokt anuchhed mein di gayi dhaatuon mein se ho, ek ya adhik ka upayog akalush ispaat ke gunon mein thoda sa parivartan laane ke liye kiya gaya ho.

(4) jinmein kromiym aur nikal ka upayog pramukh dhaatu-mishranakaari ke roop mein kiya gaya ho.

(5) jinmein nikal ke sthaan par pramukh dhaatu-mishranakaari ke roop mein mainganeej ka upayog kiya gaya ho aur vaisa hi akalush ispaat banaaya gaya ho jaisa anachhed (3) aur (4) mein varnit hai.

kaarban ki maatra ya dhaatveeya sanrachana ki drushti se bhi ispaat ka vargeekaran kiya ja sakta hai. inmein se pratyek reeti mein ispaat ka teen vargon mein vibhaajan kiya jaata hai. kaarban ke anusaar vargeekaran karne par ispaat nyoon, madhyam aur uchch kaarbanavaale ispaat kahalaate hain. sanrachana ki drushti se bhi ispaat ko teen vargon mein baaaintate hain:

(1) feritik ispaat, jo kade kiye hi nahi ja sakte. inmein 15 pratishat se 30 pratishat tak kromiym rahata hai aur kaarban ki maatra bahut kam (0.08 se 0.20 pratishat tak) rahati hai.

(2) maarateinsitik ispaat, jo tapt karke paani mein bujhaane par kade ho jaate hain. inmein 10 pratishat se 18 pratishat tak kromiym rahata hai aur 0.08 pratishat se 1.10 pratishat tak kaarban.

(3) aastenitik ispaat, jo bina bujhaae hi kada kiya ja sakta hai. ismein 16 pratishat se 26 pratishat tak kromiym aur 6 pratishat se 22 pratishat tak nikal rahata hai.

paralaitik ispaat kathor kiya ja sakta hai aur aisa karne par usaki sanrachana maarateinsitik ke samaan ho jaati hai.

kromiym ispaat mein kshaya-pratirodh-shakti baahya tal par lauhakromiym aaksaaid ki patali sthaayi parat ban jaane ke kaaran utpann hoti hai. yeh patali parat apne neeche sthit ispaat ke kshaya ko rokati hai. yadi raasaayanik kriya ya ragad se yeh tah nasht ho jaati hai to avilanb uske neeche aisi hi doosari tah ka nirmaan ho jaata hai. uchch taap par bhi yeh tah drudhta se chipki rah jaati hai aur aakseekaran ko rokati hai. lauh ko nishkriya banaane ke liye kromiym ki nyoonatam maatra 12 pratishat hai. dhaatu-mishranakaari ke roop mein kromiym aur nikal athva kromiym aur mainganeej milaakar bane akalush ispaaton ke gun "feritik" aur saadhaaran kromiym ispaat se bhinn hote hain. ye ispaat taar kheenchne yogya, achunbakeeya aur thandi vidhi ko chhod anya vidhiyon se kathor na honevaale varg mein aate hain. sanrachana mein ye aastenitik ispaat ke samaan hain. kshayanirodhakata ki drushti se kromiym mainganeej ispaat ki mishr dhaatu kromiym-nikal-ispaat ki mishr dhaatu se nirbal, kintu utane hi kromiymavaale ispaat ki mishr dhaatu se sabal hoti hai. Bhaarat mein kromiym aur mainganeej ki bahulata ki drushti se yeh tathya audyogik mahatva ka hai.

vyaavahaarik roop se lagbhag sampoorn akalush ispaat bijli ki bhatthi mein banaaya jaata hai. thoda sa bhaag pravartan bhatthiyon (indakshan faneinsej) aur aark-bhatthiyon mein banaaya jaata hai. kachche lohe ke tukade bhatthi mein pighlaae jaate hain aur aakseejan ki sahayata se shodhit kar liye jaate hain. ismein kromiym daalne ke liye kaarban ki kam maatraavaali lauhakromiym mishr dhaatu pighle lauh mein milaai jaati hai. fir usamein nikal ya mainganeej milaaya jaata hai. anya dhaatueain bhi aavashkataanusaar bhatthi mein mila di jaati hain. tab pighle hue, shodhit aur vidhivt nirmit mishr dhaatu ki silein dhaal li jaati hain. in silon ko peetakar ya belakar chhadon ke roop mein bana liya jaata hai. anya prakaar ke ispaaton ki apeksha akalush ispaat mein nirmaan ki kriyaaeain, yatha baahya tal ka niyantran, ghisna, retana, baahya tal par aakseekaran rokane ke liye pun: garam karna, ardhanirmit vastuon par ret ki dhaar maarana aur aml se svachh karna aadi kriyaaeain, adhik maatra mein ki jaati hain. iske atirikt akalush ispaat ke upakaranon ke oopari prushth ko log vibhinn avasthaaon mein chaahate hain, yatha mrudu, kathor, chamakarahit se lekar shreshth paalishvaale tak aur khuradure se lekar poornataya suchikkan tak.

jahaaain nimnalikhit avasthaaon mein se ek ya adhik avasthaaon ka nirvaah safalataapoorvak karna padta hai vahaaain akalush ispaat ki aavashyakta padti hai : pratikool ritu, dhool, khatta ya namakeen bhojan, raasaayanik padaarth, dhaatuon ko haani pahuainchaanevaale jeevaanu, jal, gharshan, aaghaat aur agni. iska upayog vahaaain bhi kiya jaata hai jahaaain baahya tal ko svaasthya ki drushti se svachh, sundar ya suchikkan rakhana hota hai. jahaaain majabooti ki aavashyakta hoti hai vahaaain bhi iska upayog kiya jaata hai.

akalush ispaat ko chamakadaar rakhane ke liye saadhaaran paalish ya bijli ki kalai ki aavashkata naheen hoti, keval samay-samay par saadhaaran safaai hi paryaapt rahati hai. akalush ispaat ki visheshata usamein jang na lagne, kshaya na hone aur rang mein vikruti na hone ke kaaran hai. saadhaaranat: pratirodhashakti kromiym ansh ke anusaar badalti hai. aastenitik 18 : 8 vaale akalush ispaat mein (jismein 18 pratishat kromiym aur 8 pratishat nikal rahata hai) ritukshaya se bachane aur bhojanaalaya ke, kapda dhone ke tatha dugdhashaala ke bartanon aur anya saadhaaran upayogon ke nimitt uttam pratirodhashakti rahati hai. iske gun 14 : 18 kromiym-ispaat ke samaan hote hain jinmein kaarban ki maatra 0.12 pratishat se adhik naheen hoti. niklavaala akalush ispaat saadhaaran akalush ispaat se kuchh hi mahainga padta hai. kromiym nikal akalush ispaat mein molibdeenam milaane se lavanon aur tejaabon ke prati pratirodhashakti badh jaati hai. isse iska upayog samudratatavarti athva lavan ke sampark mein aanevaale upaadaanon mein vishesh roop se hota hai.

kromiym-nikal akalush ispaat ko 450digri se 900digri seinteegred ke taapon ke beech upayog karne athva peetane se usaki pratirodh shakti kam ho jaati hai. is dosh ko door karne ke liye use 1,000 degree se uchch taap par garam karke pun: sheeghrata se sheetal kar liya jaata hai. kromiym-nikal aur keval kromiymavaale akalush ispaat, jinmein kaarban ki ki maatra 0.03 pratishat se 0.08 pratishat tak hoti hai aur jinko thoda sa kolanbiym, niyobiym ya taaiteniym milaakar sthaayi kiya jaata hai, is prabhaav se mukt rahate hain.

akalush ispaat ke raasaayanik shatru hain kloraaid, bromaaid aur aayodaaid. yadi dhaatu ko samay-samay par jal se svachh kar liya jaata hai aur hava mein sookhane diya jaata hai to vah achha kaam deti hai. yadi dhaatu par dhool athva anya padaarthon ki tah jam jaati hai jisse dhaatu se vaayu ka sampark naheen ho paata aur dhool ki tah lavanamaya jal se tar ho jaati hai to aise sthaanon par gaddhe pad jaate hain. ise rokane ke liye nimnalikhit upaaya karne chaahiye :

(1) bartanon ki sandhiyaaain gahari aur teekshn na rahein. unhein gol rakha jaae.

(2) kshayaatmak prayogon mein aanevaale upaadaanon ko bhali bhaaainti chikna karke paalish kar li jaae, visheshakar veld ki gayi sandhiyon ko.

(3) chhanane aur jaaleedaar tokariyon ko vishesh roop se svachh kiya jaae jisse jaaliyon ke beech gard na jamane paae.

(4) nirmaan ke samay lage hue lauhakan aur papadiyaaain ghiskar saaf kar di jaaeain.

(5) kshayakaari vaataavaran mein garam kiye jaanevaale saamaanon ke banaane mein is baat ka dhyaan rakha jaae ki unke vibhinn avayavon ke prasaar ke liye paryaapt sthaan rahe.

chaap sahanevaale vaalv, panp aur nal ki fiting, jinhein 550 degree seinteeged se ooainche taap par kaam mein laana hota hai, vishvaneeya majabooti ke liye akalush ispaat ke banaae jaate hain. bhatthiyon ke bhaagon mein, daahak kakshon mein, chimniyon ke astar mein aur isi prakaar ke anya kaaryon mein akalush ispaat ka upayog kiya jaata hai. saadhaaran ispaat par jami aaksaaid ki parat saralata se chhoot padti hai, par akalush ispaat ki aaksaaid ki parat iski tulana mein sthaayi hoti hai aur neeche ki dhaatu ki raksha karti rahati hai.

bahut thandi karne par adhikaansh dhaatueain churamuri ho jaati hain, kintu kromiym niklavaale ispaat drav aakseejan ke taap tak drudh, taar kheenchne yogya aur aaghaatasah bane rahate hain. isliye udyogon mein is shreni ke nimn taap par isi dhaatu ka prayog kiya jaata hai.

anya dhaatuon ki apeksha akalush ispaat ko bahudha kam kharch mein hi sookshm evam drudh roop diya ja sakta hai. iske taar usi sugamata se kheenche ja sakte hain jis sugamata se taamr ya peetal ke, par yeh saadhaaran ispaat se adhik drudh hote hain. apni is drudhta ke kaaran akalush ispaat ke upaadaanon ko roop dene mein adhik shakti, bade yantron aur adhik shram ki aavashyakta hoti hai. yadi atyadhik drudh upaadaan nirmit karna ho to ispaat ko beech-beech mein mrudu banaane ki kriya karni padti hai. akalush ispaat se vividh saamagri banaane mein ki jaanevaali pramukh kriyaaeain ye hain : modna, gol karna, taar kheenchna, peetana, ainthana, taanana aur nali banaana.

yadi saavadhaani se kaarya kiya jaae to akalush ispaat ke liye vyaavasaayik veÏaaldag ki sabhi prachalit reetiyaaain kaam mein laai ja sakti hain. pighlaakar jodne (veld karne) mein aapse aap ban jaanevaali goliyon ko ghiskar atyant chikna kar liya jaata hai jisse jod dekhne mein sundar lage aur svaasthya ke liye hitkar rahe. sunirmit, svachaalit, nishkriya gaison mein sanrakshit, "aark" bhatthi par veld kiye hue akalush ispaat bijli dvaara paalish karne dene se saadhaaranat: paryaapt chikne ho jaate hain. sabhi prakaar ke kromiym-nikal akalush ispaat veÏaaldag ke taap par utpann honevaale vikrutikaari prabhaavon ke hote hue bhi taar kheenchne yogya rahate hain. veld karte samay sandhi ke aaspaas bani goliyaaain bhi mrudu, pusht aur pit sakane yogya rahati hain. yadi aisitileen veÏaaldag theek se na ki jaae to sandhi mein kaarban ka samaavesh ho jaane se pushtata kshayanirodhakata mein kami aa jaati hai.

kathor banaane yogya akalush ispaaton ki bhi veÏaaldag ki ja sakti hai, kintu unhein vishesh kriyaaon dvaara joda jaata hai, jisse ve chitk na jaaeain. aise ispaaton ko, jinmein kaarban ki maatra 0.20 pratishat se adhik ho, pehle 260roo sein. tak garam kar liya jaata hai, fir unhein usi taap par veld karke mrudu bana liya jaata hai. yadi veÏaaldag ke pashchaat turant hi dhaatu ko kathor karna aur usapar paani chadhaana ho to mrudu banaane ki kriya chhodi ja sakti hai. saadhaaranat: aise purajon ko veÏaaldag dvaara naheen jodna chaahiye jinpar bahut thonk peet ya kataai karni ho.

akalush ispaat ke tukade saadhaaranat: takkari jod (bat veÏaaldag) se jode jaate hain. patali vastueain ek ke oopar ek chadhaakar veÏaaldag dvaara jodi jaati hain. tank aur refrijretar aadi ki jodaai seem veÏaaldag se ki jaati hai.

akalush ispaat ko jodne mein raaainge-seese ke taaainke ka upayog kadaapi na karna chaahiye. akalush ispaat ko doosari dhaatuon se jodne ke liye chaaaindi ka taaainka lagaaya jaata hai, kintu yadi yeh kriya sheegra sampann na ki ja sake to ismein maalibdeenam aadi pade susthir akalush ka hi upayog karna chaahiye.

adhikaansh praamaanik akalush ispaaton ko kharaadane aadi mein badi kathinaai padti hai. dhaatu ke nikaale gaye ansh lambe-lambe chimde tukadon mein nikalte hai jinse pareshaani hoti hai. gandhak athva seleeniym ki kuchh adhik maatra akalush ispaat mein milaakar is dosh se mukt sankar dhaatu ka nirmaan kiya ja sakta hai.

tapt karke kisi bhi prakaar ke akalush ispaat ko thonk peetakar ichhit aakaar diya ja sakta hai. yadyapi akalush ispaat ko dhaala ja sakta hai, fir bhi patali ya moti chaadarein jodkar hi vibhinn vastueain banaane ki pratha adhik prachalit hai. yadi akalush ispaat se sookshm yantr banaane hon to iske liye vishesh prakaar ke daabanevaale saaainchon ka upayog kiya jaata hai.

kshayanirodhak chhanane aur isi prakaar ke anya niyantrit randhronvaale yantr banaane ke liye choorn akalush ispaat ko vishesh dhang ke saaainchon mein atyant adhik daab se dabaaya jaata hai.

peinch, sitkini, rivit aadi ko, jinka upayog akalush ispaat ki vastuon ke sanyog ke liye kiya jaae, akalush ispaat ka banaana chaahiye.

kromiym-nikal akalush ispaat ko atyadhik kathor banaaya ja sakta hai. mrudu kiye gaye sab prakaar ke akalush ispaat saadhaaran ispaat se adhik majaboot hote hain. kathor karne par ve aur bhi majaboot ho jaate hain. thandi avastha mein hi belane ya taar kheenchne se 18 : 8 vaale akalush ispaat ki majabooti prati varg inch kai sau tan hoti hai. thandi dasha mein tanaav dekar banaae gaye kromiym-nikal akalush ispaat ki chaddaron ko spot veÏaaldag dvaara jodkar aisi dharanein banaai ja sakti hain jinka upayog anya halki sankar dhaatuon ke sthaan par yaataayaat udyog athva aise nirmaan kaaryon mein laabh ke saath ho sakta hai jahaaain halki dhaatu ka upayog nitaant aavashyak hota hai.

neeche di hui taalika vibhinn prakaar ke akalush ispaat aur unke upayogon ko vyakt karti hai :

(1) 12 pratishat kromiym saadhaaran kaamon ke liye; koyale ke kshetr mein; prayukt yantraadi mein; panp, vaalv aadi mein.

(2) 17 pratishat kromiym

• tapt kathor ho sakanevaala chhuri, kaaainta aadi; shastrachikitsa ke aujaar, baal beyaring aadi mein.

• kathor na ho sakanevaala gruhanirmaan (aaaintarik); motarakaar; daahak kaksh mein.

(3) 18 : 8 kromiym-nikal bhojan, bhojanaagaar, gruhon ke baahari darvaajon ya deevaaron mein.

(4) 18 : 8 kromiym-nikal-maalibdeenam lavanamaya jal; vastranirmaan ke yantr, kaagaj nirmaan ke yantr; ya fotograafi mein.

(5) kromiym-mainganeej bhojanaagaar, gruh ke baahari upakaran aur baahya deevaaron mein.

suchikkan akalush ispaat sabse achha kshayanirodhi hai. akalush ispaat ke bane paatron ke bheetari kone gol rakhe jaate hain. sarvaadhik kshayapratirodh-shakti praapt karne ke liye akalush ispaat ko 20-40 pratishat shore ke aml mein 55digri sein. se 70digri sein tak taap par kam se kam aadhe ghante tak dubaakar rakha jaata hai.