MATERIAL DATA SHEET

Rectangular Hollow Sections (RHS), Grade 350, various sizes (Specified by size & wall thickness)

Ferrous Structural
mineral › Metallic › Ferrous Structural
mineralmetallicstructural-steelhollow-sectiongrade-350AS-NZS-1163cold-formedRHSconstructionrecyclable
ATLAS CODE
MIN-MET-FER-007
Rectangular Hollow Sections (RHS), Grade 350, various sizes (Specified by size & wall thickness)
Category mineral
Material Family Metallic
Regulatory Status Non-combustible
Density
7850 kg/m³
Carbon (A1-A5)
14.5 kgCO₂e
Fire Class
Non-combustible
Lifespan
50-100 yrs
Description

RHS Grade 350 are cold-formed, electric resistance-welded steel hollow sections manufactured to AS/NZS 1163:2016. The '350' designation indicates a minimum yield strength of 350 MPa, making these sections suitable for high-strength structural applications. The rectangular profile offers excellent torsional rigidity and compression resistance, with standard sizes ranging from 50x20mm to 400x300mm with wall thicknesses from 1.6mm to 16mm. The material features a ferrite-pearlite microstructure providing optimal strength and ductility for welding and fabrication.

Primary Sectors
[Commercial][Industrial][Transport & Infrastructure]
Typical Uses
  • Structural frames in commercial and industrial buildings
  • Column and beam applications in multi-storey construction
  • Roof trusses and portal frames
  • Architectural features and exposed structural elements
  • Seismic bracing systems
  • Bridge and infrastructure components
  • Temporary structures and scaffolding systems
  • Agricultural and mining equipment frames
  • Bollards and protective barriers
Recycled Content 25
Renewable Content 0
Recyclability 100
Embodied Carbon 14.5 kgCO₂e
Embodied Energy 25 MJ/kg
EPD Available Yes
Advantages
High strength-to-weight ratio optimising structural efficiencyExcellent torsional rigidity and buckling resistanceSuitable for welding with standard proceduresConsistent mechanical properties through cold-forming process100% recyclable with established recycling infrastructureAvailable in dual-grade options (C350/C450) for design flexibilityCompatible with all standard connection methodsAesthetic appeal for architectural exposed applicationsLower embodied carbon than concrete alternatives
Cautions
Requires fire protection for rated assembliesSusceptible to corrosion without protective coatingsThermal bridging in building envelope applicationsHigher initial cost than timber alternativesLimited availability of very large sectionsRequires skilled labour for complex connectionsCold-forming limits to maximum wall thicknessPotential for galvanic corrosion with dissimilar metals
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TECHNICAL DATA: PERFORMANCE PROPERTIES MIN-MET-FER-007
Density (Dry) 7850 kg/m³
Specific Gravity 7.85
Porosity 0 %
Water Absorption 0 %
Hardness 150
Surface Roughness 3.2 μm
UV Resistance High
Chemical Resistance Moderate
pH Tolerance 4-10
Compressive Strength 350 MPa
Tensile Strength 430 MPa
Flexural Strength 350 MPa
Shear Strength 200 MPa
Elastic Modulus 200000 GPa
Yield Strength 350 MPa
Impact Resistance 27 J/m
Bearing Capacity 525 kN/m²
Poisson's Ratio 0.3
Creep Resistance Negligible below 400°C
Abrasion Resistance High
Thermal Conductivity 45 W/mK
Thermal Resistance 0.022 m²K/W
Specific Heat Capacity 450 J/kgK
Thermal Expansion 11.7 μm/m·K
Melting Point 1425 °C
Noise Reduction Coeff. (NRC) 0.05
Optical
Light Transmittance 0 %
Light Reflectance (LRV) 25 %

Cold-formed hollow sections were introduced to Australia in the 1960s, initially as imported products. Local manufacturing commenced in the 1970s with the establishment of tube mills in major cities. The development of AS/NZS 1163 in 1991 (replacing AS 1163) standardised grades and properties. Grade 350 became the standard structural grade in the 2000s, replacing earlier Grade 250 for most applications. Recent developments include dual-grade products (C350/C450) and improved corrosion protection systems. The 2016 revision of AS/NZS 1163 introduced mandatory Factory Production Control requirements, enhancing quality assurance. Current focus areas include reducing embodied carbon through increased recycled content and renewable energy in production.

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SAFETY, ECOLOGY & INSTALLATION MIN-MET-FER-007
Flame Spread Index 0
Smoke Developed Index 0
Combustibility Class Non-combustible
Fire Resistance Rating 0/-/- unprotected; up to 240/-/- with intumescent coating hours
Heat Release Rate 0 kW/m²
Toxicity of Combustion None
Embodied Carbon (A1-A3) 14.5 kgCO₂e/kg
Embodied Energy 25 MJ/kg
Water Footprint 28 L/kg
EPD Available Yes
Recycled Content 25%
Renewable Content 0%
LEED Points 2
Circular Economy Score 85 /100
VOC Emissions 0 g/L
Skill Level Qualified structural steel fabricator/erector
Crew Size 3
Installation Time 0.5-2.0 hours/m depending on complexity hr/m²
Temperature Range -10 to 45 °C
Humidity Range 0-100 %
Required Tools
MIG/TIG welding equipmentAngle grinder with cutting discsMagnetic drill for bolt holesCold saw or band saw for precision cuttingCrane or lifting equipment for large sections
Certifications Required
AS/NZS 1554 welding qualificationWhite Card (construction induction)EWP licence for elevated workStructural steel erection licence (state-specific)
Weather Limitations
Wind speed >30km/h for crane liftsElectrical storms for welding operationsExtreme heat >40°C affecting worker safety
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COMMERCIAL, LOGISTICS & REGULATORY MIN-MET-FER-007
Material Cost 1800-2500
Installation Cost 120-180
Annual Maintenance 2-5
Lifecycle Cost (50yr) Competitive over 50+ year design life
Market Availability Readily available
Lead Time 1-3 days ex-stock, 2-4 weeks fabricated weeks
Design Life 50-100 years
Warranty Period 10-25 years
Maintenance Interval 5-10 months
Service Temp Range -40 to 400 °C
Freeze/Thaw Resistance Excellent
Dimensional Stability Excellent below 100°C
Certifications Held
AS/NZS 1163:2016 - Cold-formed structural steel hollow sectionsFactory Production Control certificationACRS certification (manufacturer specific)EPD to ISO 14025 and EN 15804Green Star compliant productResponsibleSteel certification (manufacturer specific)No health hazards in normal useSDS available from manufacturers
Fire Code Compliance
AS 1530.4:2014 - Fire resistance testsAS 4100:2020 Section 12 - Fire design
Standards Compliance
NCC 2022 Volume One - Structural provisionsNCC 2022 Section C - Fire resistanceDeemed-to-Satisfy via AS 4100:2020Equivalent to ASTM A500 Grade BISO 630-2 - Structural steelsISO 14025 - EPD complianceComparable to EN 10219 S355

DISCLAIMER: This specification document is generated from the CLAD Materials Atlas Database. Information is for general guidance only and does not constitute professional engineering advice. Values are typical and may vary by batch, manufacturer, and production run. Verify suitability for specific project applications independently.

ID: MIN-MET-FER-007 Schema: v3.0
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