309/309S vs. 310/310S pada suhu tinggi

Resistensi oksidasi 309/309S vs. 310/310S pada suhu tinggi

Oxidation and Baja Tahan Karat

Under most conditions, paduan logam bereaksi dengan lingkungannya. The most common reaction is oksidasi, where metals combine with oxygen to form oxides.

In stainless steel, kromium helps resist oxidation. A thin, stable chromium oxide layer (Cr₂O₃), called chromia, is formed on the surface. This layer grows slowly and adheres well to the metal, preventing faster-forming oxides from developing.

	Jenis 309 (UNSS30900)	Type 309S (KITA S30908)	Type 309H (KITA S30909)	Type 309Si (DARI 1.4828)	Jenis 310 (KITA S31000)	Type 310S (KITA S31008)	Type 310H (KITA S31009)	Type 310Si (DARI 1.4841)
C	0.2	0.08	0.04 menit 0.10 maks	0.2	0.25	0.08	0.04 menit 0.10 maks	0.2
N	—	—	—	0.11	—	—	—	0.11
M N	2	2	2	2	2	2	2	2
P	0.045	0.045	0.045	0.045	0.045	0.045	0.045	0.045
S	0.03	0.03	0.03	0.015	0.03	0.03	0.03	0.015
DAN	0.75	0.75	0.75	1.50 menit 2.50 maks	1.5	1.5	0.75	1.50 menit 2.50 maks
Kr	22.00 menit 24.00 maks	22.00 menit 24.00 maks	22.00 menit 24.00 maks	19.00 menit 21.00 maks	24.00 menit 26.00 maks	24.00 menit 26.00 maks	24.00 menit 26.00 maks	24.00 menit 26.00 maks
Di dalam	12.00 menit 15.00 maks	12.00 menit 15.00 maks	12.00 menit 15.00 maks	11.00menit 13.00 maks	19.00 menit 22.00 maks	19.00 menit 22.00 maks	19.00 menit 22.00 maks	19.00 menit 22.00 maks
Fe	Keseimbangan	Keseimbangan	Keseimbangan	Keseimbangan	Keseimbangan	Keseimbangan	Keseimbangan	Keseimbangan

How Protection Works

Once a thick and stable chromium oxide layer is formed, it blocks further oxidation. As the layer grows thicker, oxidation slows down. This is because oxygen and metal ions must travel farther through the oxide layer.

This behavior is called protective scale formation. It is similar to the pasif process seen in corrosion at lower temperatures.

Alloy Composition and Oxidation Resistance

Itu kandungan kromium in stainless steel plays a key role in high-temperature oxidation resistance.

Alloys with at least 20% kromium are usually considered heat-resistant.
Replacing iron with nickel can also improve high-temperature performance.

309/309S vs. 310/310S

Keduanya KAMI PUNYA 309 dan ATI 310 adalah highly alloyed austenitic stainless steels. Because of their composition, they offer excellent resistance to oxidation, especially at elevated temperatures.

How Oxidation Is Measured

The resistance to oxidation is often measured by tracking weight gain after exposure to high heat.

When a metal oxidizes, it absorbs oxygen and becomes heavier.
More weight gain usually means more oxidation and lower resistance.
Less weight gain suggests better protection and higher resistance.

Ringkasan

Singkatnya:

309/309S dan 310/310S membentuk lapisan pelindung kromium oksida.
Kadar kromium dan nikel yang lebih tinggi meningkatkan ketahanan oksidasi.
310/310S, memiliki lebih banyak unsur paduan, biasanya bekerja lebih baik pada suhu yang sangat panas.
Pengujian perubahan berat digunakan untuk membandingkan kinerja oksidasinya dari waktu ke waktu.