wanhe

XI’AN WAN HE METALLURGICAL TECHNOLOGY CO.,LTD.

 

西安万合冶金技术有限公司

Tel: (0086)29-83656476    (0086)13891958911

E-mail: whyj818@163.com     liumq422@163.com

 

  • 万合冶金

    万合冶金

  • 万合冶金

    万合冶金

  • 万合冶金

    万合冶金

ABOUT US

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12 years, leading position in accumulation industry
10 years, leading position in accumulation industry
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Aggregate more than 40 senior engineers and technicians
Bringing together more than 200 senior legal experts
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Providing quality services to more than 100 families
More than 2600 legal services have been provided to the government, enterprises and individuals
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The company develops and develops equipment production line
More than 40 national and provincial honors have won the honor of "National Excellent Law Firm" for many times.

Xi'an Wan he Metallurgy Technology Co., Ltd. mainly engaged in metallurgical engineering and equipment development, development, integration and technical services, is a collection of scientific research, production as one of the high-tech private enterprises. 

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PRODUCT DISPLAY

VISION

Common Problems and Preventive Measures of Stainless Steel Surface Treatment
Stainlesssteelhasuniquestrength,highwearresistance,superioranti-corrosionperformanceandnoteasytorustandotherexcellentcharacteristics.Therefore,itiswidelyusedinchemicalindustry,foodmachinery,mechanicalandelectricalindustry,environmentalprotectionindustry,householdappliancesindustryandhouseholddecoration,decorationindustry,givingpeopleamagnificentandnoblefeeling.Theapplicationprospectsofstainlesssteelwillbewiderandwider,buttheapplicationdevelopmentofstainlesssteellargelydeterminesthedevelopmentdegreeofitssurfacetreatmenttechnology.1.CommonsurfacetreatmentmethodsforstainlesssteelIntroductionof1.1StainlessSteelVarieties1.1.1Stainlesssteelmaincomponents:generallycontainschromium(Cr),nickel(Ni),molybdenum(Mo),titanium(Ti)andotherhigh-qualitymetalelements.1.1.2Commonstainlesssteel:chromiumstainlesssteel,containingmorethan12%ofchromium;nickel-chromiumstainlesssteel,containing18%ofchromiumand12%ofnickel-chromium.1.1.3Classifiedfromthemetallographicstructureofstainlesssteel:austeniticstainlesssteel,suchas1Cr18Ni9Ti,1Cr18Ni11Nb,Cr18Mn8Ni5.Martensiticstainlesssteel,suchasCr17,Cr28,etc.Generallyknownasnon-magneticstainlesssteelandstainlesssteelwithmagnetic.1.2CommonSurfaceTreatmentofStainlessSteelThecommonsurfacetreatmenttechnologiesofstainlesssteelareasfollows:1)whiteningtreatmentoftheoriginalcolorofthesurface;2)mirrorbrighteningtreatmentofthesurface;3)surfacecoloringtreatment.1.2.1Surfacewhiteningtreatment:Duringtheprocessofstainlesssteelprocessing,blackoxideskinisproducedbyrolling,edgebinding,weldingorartificialsurfaceheatingtreatment.Thiskindofhardgray-blackoxideskinismainlycomposedofNiCr2O4andNiFEO4,whichwereusuallyremovedbystrongcorrosionwithhydrofluoricacidandnitricacidbefore.Butthismethodisexpensive,pollutingtheenvironment,harmfultohumanbody,corrosiveandgraduallyeliminated.Atpresent,therearetwomainmethodstotreatoxideskin:(1)Sandblasting(pellet)method:mainlyusingthemethodofsprayingglassbeadstoremovetheblackoxideskinonthesurface.(2)Chemicalmethod:Anon-pollutingpicklingpassivatingpasteandanon-toxiccleaningsolutionwithinorganicadditivesatroomtemperaturewereusedforleaching.Soastoachievethepurposeofwhiteningstainlesssteel.Aftertreatment,itbasicallylookslikeadullcolor.Thismethodismoresuitableforlargeandcomplexproducts.1.2.2Surfacemirrorpolishingtreatmentofstainlesssteel:Accordingtothecomplexityofstainlesssteelproductsanduserrequirements,mechanicalpolishing,chemicalpolishing,electrochemicalpolishingandothermethodscanbeusedtoachievemirrorgloss.Theadvantagesanddisadvantagesofthesethreemethodsareasfollows:1.2.3Surfacecoloringtreatment:StainlessSteelColoringnotonlygivesstainlesssteelproductsavarietyofcolors,increasethevarietyofproducts,butalsoimprovethewearresistanceandcorrosionresistanceofproducts.ThereareseveralStainlessSteelColoringmethodsasfollows:(1)Chemicaloxidationcoloringmethod;(2)electrochemicaloxidationcoloringmethod;(3)Iondepositionoxidecoloringmethod;(5)Hightemperatureoxidationcoloringmethod;_Gasphasepyrolysiscoloringmethod.Abriefoverviewofthevariousmethodsisasfollows:(1)Chemicaloxidationcoloringmethod:inaspecificsolution,thecolorofthefilmisformedbychemicaloxidation,includingdichromatemethod,mixedsodiumsaltmethod,sulfurizationmethod,acidoxidationmethodandalkalineoxidationmethod.Generally,INCOiswidelyused,butifyouwanttoensurethatabatchofproductshavethesamecolor,youmustusereferenceelectrodestocontrolit.(2)Electrochemicalcoloring:Thecolorofthefilmisformedbyelectrochemicaloxidationinaspecificsolution._Iondepositionoxidescoloringchemicalmethod:thatis,stainlesssteelworkpiecesareplacedinavacuumcoatingmachineforvacuumevaporationplating.Forexample:Titanium-platedwatchcase,watchband,generallygolden.Thismethodissuitableformassproductprocessing.Becauseoflargeinvestmentandhighcost,smallbatchproductsarenoteconomical.(4)Hightemperatureoxidationcoloringmethod:inaspecificmoltensalt,theworkpieceisimmersedinacertainprocessparameters,sothattheworkpieceformsacertainthicknessofoxidefilm,andpresentsavarietyofdifferentcolors._Gasphasepyrolysiscoloringmethod:morecomplex,lessusedinindustry.Selectionof1.3TreatmentMethodWhichmethodtochooseforsurfacetreatmentofstainlesssteelshouldbeselectedaccordingtoproductstructure,materialqualityanddifferentrequirementsforsurface.2.Commoncausesofcorrosionofstainlesssteelparts2.1ChemicalCorrosion2.1.1SurfacePollution:Oil,dust,acid,alkaliandsaltattachedtothesurfaceoftheworkpiecearetransformedintocorrosivemediumundercertainconditions,andreactwithsomecomponentsofstainlesssteel,resultinginchemicalcorrosionandrusting.2.1.2Surfacescratches:Thedamageofvariousscratchestopassivationfilmreducestheprotectiveabilityofstainlesssteel,andiseasytoreactwithchemicalmedia,resultinginchemicalcorrosionandrusting.2.1.3Cleaning:Afterpicklingpassivation,cleaningisnotclean,resultinginresidualliquidretention,directcorrosionofstainlesssteel(chemicalcorrosion).2.2electrochemicalcorrosion2.2.1Carbonsteelpollution:scratchescausedbycontactwithcarbonsteelpartsandgalvaniccellsformedbycorrosivemediumleadtoelectrochemicalcorrosion.2.2.2Cut
2019-01-17
Properties and Microstructure of Stainless Steel
Atpresent,therearemorethan100knownchemicalelements,andabouttwentychemicalelementscanbeencounteredinsteelmaterialscommonlyusedinindustry.Forstainlesssteel,aspecialsteelseriesformedbypeople'slong-termstruggleagainstcorrosion,therearemorethantencommonelements.Inadditiontoiron,whichisthebasicelementofsteel,themostinfluentialelementsonthepropertiesandstructureofstainlesssteelarecarbon,chromium,nickel,manganese,silicon,molybdenum,titanium,niobium,titanium,manganese,nitrogen,copperandcobalt.Exceptforcarbon,siliconandnitrogen,theseelementsarealltransitionalelementsintheperiodictableofchemicalelements.Infact,thestainlesssteelusedinindustryhasseveralormoreelementsatthesametime.Whenseveralelementscoexistinthestainlesssteelasawhole,theirinfluenceismuchmorecomplexthanthatwhentheyexistalone.Inthiscase,notonlytheeffectofeachelementitself,butalsotheinfluenceofeachothershouldbeconsidered.Therefore,thestructureofstainlesssteeldependsonallkindsofelements.Thesumoftheeffectsofelements.1.Theeffectofvariouselementsonthepropertiesandstructureofstainlesssteel1-1.ThedecisiveroleofchromiuminstainlesssteelThereisonlyoneelementthatdeterminesthenatureofstainlesssteel,chromium.Eachstainlesssteelcontainsacertainamountofchromium.Sofar,thereisnostainlesssteelwithoutchromium.Thebasicreasonwhychromiumhasbecomethemainelementdeterminingthepropertiesofstainlesssteelisthatafteraddingchromiumasalloyelementtosteel,theinternalcontradictionmovementofchromiumispromotedtodevelopinfavorofcorrosionresistance.Thischangecanbeexplainedinthefollowingaspects:(1)Chromiumincreasestheelectrodepotentialofiron-basedsolidsolution(2)ChromiumabsorbsironelectronstopassivateironPassivationisaphenomenonthatthecorrosionresistanceofmetalsandalloysisimprovedbecausetheanodicreactionisblocked.Therearemanytheoriesforpassivationofmetalsandalloys,suchasfilmtheory,adsorptiontheoryandelectronarrangementtheory.DualityofCarboninStainlessSteelCarbonisoneofthemainelementsinindustrialsteels.Thepropertiesandstructureofsteelsdependlargelyonthecontentanddistributionofcarboninsteels,especiallyinstainlesssteels.Theeffectofcarbononthestructureofstainlesssteelismainlymanifestedintwoaspects.Ontheonehand,carbonisanelementofstableaustenite,anditseffectisverylarge(about30timesthatofnickel).Ontheotherhand,becauseoftheaffinityofcarbonandchromium,itformsaseriesofcomplexcarbideswithchromium.Therefore,theroleofcarboninstainlesssteeliscontradictoryintermsofstrengthandcorrosionresistanceofcandles.Understandingthelawofthiseffect,wecanchoosestainlesssteelwithdifferentcarboncontentfromdifferentrequirements.Forexample,thestandardchromiumcontentofthefivestainlesssteelgrades,0Crl3-4Cr13,whichisthemostwidelyusedandminimuminindustry,issetat12-14%,whichisdeterminedaftertakingintoaccountthefactorsthatcarbonandchromiumformchromiumcarbide.Thepurposeisthatafterthecombinationofcarbonandchromiumintochromiumcarbide,thechromiumcontentinthesolidsolutionshouldnotbelessthan11.7%oftheminimumchromiumcontent.Forthesefivesteelgrades,becauseofthedifferentcarboncontent,thestrengthandcorrosionresistancearealsodifferent.0Cr13-2Crl3steelhasbettercorrosionresistancebutlowerstrengththan3Crl3and4Cr13steel,whicharemostlyusedtomanufacturestructuralparts.Thelattertwosteelgrades,becauseoftheirhighcarboncontent,canobtainhigherstrengthformanufacturingpartsrequiringhighstrengthandwearresistance,suchasspringsandcutters.Forexample,inordertoovercometheintergranularcorrosionof18-8Chromium-NickelStainlesssteel,thecarboncontentofsteelcanbereducedtolessthan0.03%,ortheelementswithgreateraffinitythanchromiumandcarbon(titaniumorniobium)canbeaddedtopreventtheformationofchromiumcarbide.Whenhighhardnessandwearresistancebecomethemainrequirements,wecanincreasethecarboncontentofsteelwhileappropriatelyincreasingthechromiumcontenttomeetbothhardnessandresistance.Therequirementsofabrasivenessandcorrosionresistancearealsoconsidered.Industrialbearings,measuringtoolsandbladesaremadeofstainlesssteel9Cr18and9Cr17MoVCo.Althoughthecarboncontentisashighas0.85-0.95%,therequirementofcorrosionresistanceisstillguaranteedbecausetheirchromiumcontentiscorrespondinglyincreased.Generallyspeaking,thecarboncontentofstainlesssteelusedinindustryisrelativelylow.Thecarboncontentofmoststainlesssteelrangesfrom0.1%to0.4%,whilethatofacid-resistantsteelrangesfrom0.1%to0.2%.Stainlesssteelwithcarboncontentgreaterthan0.4%onlyaccountsforasmallpartofthetotalnumberofsteelgrades.Thisisbecauseundermostoperatingconditions,stainlesssteelalwaysaimsatcorrosionresistance.Inaddition,lowcarboncontentisalsoduetosometechnicalrequirements,suchaseasyweldingandcolddeformation.1-3.Theroleofnickelinstainlesssteelisplayedonlyafteritcooperateswithchromium.Nickelisanexcellentcorrosionresistantmaterialandanimportantalloyingelementinalloysteel.Nickelisanausteniteformingelementinsteel,butthecorrosionresistanceoflowcarbonnickelsteelinsomemediawillchangesignificantlyonlywhenthecontentofnickelis27%inordertoobtainpureaustenitestructure.Sonickelcan'tbemadeofstainlesssteelalone.Butwhennickelandchromiumexistinstainlessste
2019-01-17

To provide users with high-tech, high-quality products, at the same time, "safe and reliable design, meticulous manufacturing, timely and effective service" as the company's philosophy, to "meet the needs of users, is the pursuit of Wanhe" as the purpose, to provide users with high-quality, fast and efficient services, to treat users adhere to the "honest man, serious work", to achieve the urgent needs of users, want to use All-round service for users.

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INDUSTRIAL DISTRIBUTION

The products developed by the company are exported to Romania, Indonesia, Vietnam and other countries.