SUS329J4L

HuaNickel SUS329J4L is also a super duplex stainless steel, which came out and was put on the market in 1990~1991. Compared with HuaNickel 00Cr25Ni7Mo4, the amount of molybdenum in this steel is slightly lower, but about 1.5% copper is added, so that the performance of this steel resistance to reducing acid media, such as sulfuric acid corrosion resistance, has been significantly increased, and in some environments, the performance of crevice corrosion resistance and corrosion resistance has also been improved.

SUS329J4LChemical composition：

	Cr	Ni	Mo	Cu	N	C	Si	Mn	S	P
Min	24	5.6	3	0.5	0.2	≤
Max	26	8	4	2	0.35	0.03	0.8	1.5	0.02	0.035

SUS329J4LPhysical properties：

densityp  /g ·cm-	Specific heat capacityJ/kg·℃			Wire expansion system/×10-6℃-1		Thermal conductivity/W·(m·℃)-1			Elastic modulus/MPa
	20℃	100℃	200℃	20~100	20~200	20℃	100℃	200℃	20℃	100℃	200℃
7.8	450	510	530	14.0	14.5	17	18	19	205000	195000	185000

SUS329J4LMechanical properties：

temperature/℃	σb/MPa	σp0.2/MPa	δ₅/%	Ak/J	hardness(HRC)
20	840	650	30	120	25
100	720	525	30
200	700	470	30
-20	—-		——	100
-50				80

SUS329J4LAlloy properties：

The steel also has a duplex structure of α/γ close to 1 in the structure suitable for solution treatment, but according to the continuous cooling curve of this steel, there will be intermetallic phases such as σ and x.

SUS329J4LUses of alloys：

It is mainly used in petrochemical, fertilizer and papermaking and hydrometallurgical industries to manufacture towers, tanks, pipelines, containers, heat exchangers, etc., to solve the problems of uniform corrosion and pitting, crevice corrosion and abrasion of sulfuric acid, phosphoric acid and chloride-containing media.

SUS329J4LProcess performance：

Welding process: This steel can be welded using the same process as conventional stainless steel, but GMAW, GTAW, and manual arc welding are more commonly used.

Heat treatment: The heat treatment process of this steel is heated at 1100 °C, and then quenched after heat preservation. For medium and extra-thick plates with a thickness of 35 mm and 150 mm, the cooling rate (middle part of the plate) of this steel needs to be ≥ 5000°C/h to obtain an impact energy of -50°C≥ 50J without intermetallic phase precipitation.

Relevant standards：ASTM A182M-2018