ASTM 38 NCD 4 ASTM A29 / A29M Kev Taw Qhia
Cov kev qhia tshwj xeeb tau muab faib ua plaub qhov tseem ceeb, txhua qhov uas suav nrog ntau yam kev xav tau rau cov ntaub ntawv. Tshooj I yog lub npe hu ua Tshooj Lus Qhia dav dav, thiab nws qhia txog tag nrho cov kev cai thiab cov cai uas yuav tsum tau ua kom tau raws li tag nrho cov khoom siv. Ntu II suav nrog Cov Kev Cai Kub Kub Ua Haujlwm thiab qhia txog ntau yam kev ntsuas tshuab thiab hlau uas yuav tsum tau ua kom tiav ntawm cov hlau txhawm rau txhawm rau ua kom lawv haum rau kev ua haujlwm kub. Lub caij no, Ntu III suav nrog Kev Kho Mob Thaum Tshav Kub Kub thiab qhia txog cov txheej txheem uas yuav tsum tau siv los xyuas kom meej qhov zoo ntawm cov hlau. Thaum kawg, Ntu IV suav nrog cov khoom siv kho tshuab thiab hais txog cov kev txwv uas yuav tsum tau ua raws rau txhua qib tshwj xeeb ntawm cov hlau tau teev tseg, xws li 4140, 4130, 4340, thiab 4620.
Peb lub tuam txhab tau tsim kev koom tes ntev thiab ruaj khov kev sib raug zoo nrog Tuam Tshoj Hlau thiab Hlau Association, Hlau thiab Steel Association thiab hlau thiab hlau tuam txhab uas muag thoob plaws lub xyoo, xyuas kom meej cov khoom zoo ASTM 38 NCD 4 ASTM A29 / A29M steel thiab muab tus nqi nyiam. Peb ASTM 38 NCD 4 ASTM A29 / A29M steel khoom raug xa tawm mus rau ntau tshaj 70 lub teb chaws thiab cheeb tsam txawv teb chaws thiab tau txais kev tshuaj xyuas zoo.
Daim ntawv thov:Kub forged thiab txias ua haujlwm carbon steel thiab alloy steel rods.
Thaum tshav kub kub kho:1824 degree - 1927 degree .
ASTM 38 NCD 4 ASTM A29 / A29M Tshuaj Chemical Element
Carbon, Silicon, Manganese, Phosphorus, Sulfur yog hu ua "Tsib Elements". Lawv yog cov impurities tseem ceeb hauv steel. Carbon txhim kho steel hardness. Silicon ntxiv dag zog rau cov hlau. Manganese pab txhawb kom cov hlau ruaj khov, lub zog thiab hnav tsis kam. Phosphorus txo cov hlau plasticity thiab toughness thiab tshwm txias brittleness. Lub caij no, Nws tuaj yeem ua kom muaj zog ntawm cov hlau, thiab txhim kho atmospheric corrosion stability. Sulfur ua rau kub brittleness ntawm steel siab.
| Element | Min | Max | Zoo sib xws |
|---|---|---|---|
| Mo | 0.2000 | 0.3000 | - |
| Cu | - | 0.0250 | - |
| Ni | 1.6500 | 2.0000 | - |
| Cr | 0.6000 | 0.9000 | - |
| P | - | 0.0350 | - |
| S | - | 0.0400 | - |
| Mn | 0.6000 | 0.9000 | - |
| Si | 0.1500 | 0.3500 | - |
| C | 0.3800 | 0.4300 | - |
ASTM 38 NCD 4 ASTM A29 / A29M Mechanical Properties
Kev ua haujlwm ntawm ASTM 38 NCD 4 ASTM A29 / A29M rau kev puas tsuaj hauv kev thauj khoom yog hu ua nws cov khoom siv kho tshuab. Cov khoom siv hluav taws xob ntawm cov khoom siv hlau yog lub hauv paus tseem ceeb rau kev tsim thiab xaiv cov khoom ntawm qhov chaw. Cov khoom siv ntawm cov khoom siv hlau yuav txawv nrog cov khoom sib txawv (xws li nro, compression, torsion, cuam tshuam thiab cyclic loads). Cov khoom siv kho tshuab muaj xws li lub zog, plasticity, hardness, cuam tshuam toughness, ntau yam cuam tshuam tsis kam thiab qaug zog txwv.
Cov khoom siv ntawm ASTM 38 NCD 4 ASTM A29 / A29M yog raws li ASTM A29 / A29M. Cov khoom tseem ceeb raws li hauv qab no:
| Yield Rp0.2(MPa) |
Tensile Rm(MPa) |
Kev cuam tshuam KV/Ku (J) |
Elongation A (%) |
Kev txo qis hauv ntu ntu ntawm pob txha Z (%) |
Raws li-kub-kho mob | Brinell hardness (HBW) |
|---|---|---|---|---|---|---|
| 959 (Ntau dua lossis sib npaug) | 437 (Ntau dua lossis sib npaug) | 22 | 43 | 11 | Kev daws thiab Kev laus, Annealing, Ausaging, Q + T, thiab lwm yam | 221 |
ASTM 38 NCD 4 ASTM A29 / A29M Lub cev muaj zog
Lub cev muaj zog ntawm ASTM 38 NCD 4 ASTM A29 / A29M steel suav nrog cov khoom zoo, tsis muaj qhov hnyav, khov kho, ductility thiab tiv thaiv kev yaig.
| Kub (degree) |
Modulus ntawm elasticity (GPa) |
Lub ntsiab lus coefficient ntawm thermal expansion 10-6/( degree ) ntawm 20 (degree) thiab | Thermal conductivity (W / m· degree) |
Tshwj xeeb thermal muaj peev xwm (J / kg · degree) |
Tshwj xeeb hluav taws xob resistivity (Ω mm² / m) |
Qhov ntom (kg/dm³) |
Poisson tus coefficient, ν |
|---|---|---|---|---|---|---|---|
| 21 | - | - | 0.23 | - | |||
| 747 | 164 | - | 44.3 | 224 | - | ||
| 518 | - | 43 | 22.2 | 232 | 111 |
