Steels used in braking systems

Transcription

1 Steels use in rking systems A report A mterils engineer is require to prepre report on the seletion of plin ron steels for use in the proution of vrious omponents for rke mnufturing ompny. Portions of tht report re given in this exmple. The five steels to e onsiere re; 0.1%, 0.3%, 0.6%, 0.8% n 1.2% ron steels. A report y mterils engineer Astrt: Topi: Steel use in rking systems. Investigte the ffet of miro-onstituents on the properties of steel: Five steels re to e onsiere. They re; 0.1%, 0.3%, 0.6%, 0.8% n 1.2% ron steels. The mirostrutures re shown for eh of these five steels. perlite ementite ferrite 0.1% C 0.3% C 0.6% C 0.8% C 1.2% C Figure 1.14 Steel mirostrutures Bkgroun i The miro-onstituents. There re only two phses present, ferrite n ementite. Perlite, lmell struture of lternting pltes of ferrite n ementite phses is miro-onstituent of ll of the mirostrutures. ii The properties of eh of the phses. Ferrite: is soft, mllele n utile. Cementite: is very hr n rittle. iii The struture of perlite n the phses tht re present in perlite. Perlite, is lmell struture of lternting pltes of ferrite n ementite phses. Perlite is miro-onstituent of ll of the mirostrutures, n ppers in the mirostrutures s finger print pttern. The steels Eh of the five steels will e ompre y: listing two mehnil properties of the steel explining in terms of the mirostruture why the steel possesses these properties stting two methos tht my e use to moify these properties ientifying one exmple of where the steel oul e use in rkes. 0.1% ron steel Two mehnil properties mllele n utile.

2 Mirostruture/properties the mirostruture onsists minly of ferrite grins, with smll mount of perlite in the form of pltes of ferrite n ementite. The ferrite is soft, utile n mllele, n s the ferrite is the ontinuous phse, n the preominte phse, the mehnil properties re those of ferrite. Moifition of properties the properties n e moifie y ol working or lloying. The steel nnot e hrene y het tretment. Use in rke systems king plte for iss n ps. 0.3% ron steel Two mehnil properties utile n tough. Mirostruture/properties the mirostruture onsists minly of ferrite grins, with pproximtely 30% of perlite in the form of pltes of ferrite n ementite. The ferrite is soft, utile n mllele, n is still the ontinuous phse. Due to the inrese mount of ementite the UTS n hrness is higher thn tht of the 0.1% C steel. Moifition of properties the properties n e moifie y ol working or lloying. The steel nnot e hrene y het tretment. Use in rke systems nuts n olts. 0.6% ron steel Two mehnil properties hr n tough. Mirostruture/properties the mirostruture onsists of ferrite grins, with pproximtely 75% of perlite in the form of pltes of ferrite n ementite. The ferrite is soft, utile n mllele, n is still the ontinuous phse. Due to the inrese mount of ementite the UTS n hrness re higher thn tht of the 0.3% C steel. Moifition of properties the properties n e moifie y using het tretment to hren n temper the steel. Alloying n lso e use. Use in rke systems rke springs. 0.8% ron steel (Eutetoi steel) Two mehnil properties very hr with high tensile strength. Mirostruture/properties the mirostruture onsists of perlite in the form of pltes of ferrite n ementite. Due to the inrese mount of ementite n its istriution throughout the mirostruture, the UTS n hrness re very high. Moifition of properties the properties n e moifie y using het tretment to hren n temper the steel. Alloying n lso e use. Use in rke systems rke le wire.

3 1.2% ron steel Two mehnil properties very hr with very low utility, tht is, it is very rittle. Mirostruture/properties the mirostruture onsists of perlite grins in the form of pltes of ferrite n ementite, surroune y ontinuous phse of ementite. Due to the inrese mount of ementite n its istriution throughout the mirostruture s ontinuous phse, the hrness is very high, n utility very low. Moifition of properties the properties n e moifie y using het tretment to hren n temper the steel. Alloying n lso e use. Use in rke systems ll erings. Conlusion n reommentions The five steels ll hve pplitions for the rking systems eing evelope. The vrious pplitions re liste for eh steel. It is reommene tht the steels ontinue to e use for these pplitions.

4 Steels use in rking systems- Stuent Exerise A mterils engineer hs to prepre report on the seletion of plin ron steels for use in the proution of vrious omponents for rke mnufturing ompny. Assume tht you re the engineer, omplete the unfinishe setions of the report. The report must e le to e interprete y ll of the iretors. Drw the mirostrutures for the following steels; 0.15%; 0.35%; 0.8% n; 1.1% ron steels. 0.15% C 0.35% C 0.8% C 1.1% C e Lel the phses present in eh mirostruture. Outline the properties of oth of the phses liste elow. Ferrite: Cementite: Desrie the struture of perlite, n nme the phses tht re present in perlite. For eh of the four steels nominte: i. list two mehnil properties of the steel ii. explin in terms of the mirostruture, why the steel possesses these properties iii. write two methos tht my e use to moify these properties iv. give one exmple where the steel oul e use in rkes. i ii iii iv 0.15% ron steel Two mehnil properties: Mirostruture/properties: Moifition of properties: Use in rke systems:

5 0.35% ron steel i Two mehnil properties: ii Mirostruture/properties: iii Moifition of properties: iv Use in rke systems: 0.8% ron steel (Eutetoi steel) i Two mehnil properties: ii Mirostruture/properties: iii Moifition of properties: iv Use in rke systems: 1.1% ron steel i Two mehnil properties: ii Mirostruture/properties:

6 iii iv Moifition of properties: Use in rke systems: