Table of Contents
1.What is SWRCH35K Steel?
SWRCH35K is a medium-carbon,cold heading quality carbon steel wire rod specified by the Japanese JIS standard(JIS G3507-1).It is primarily used in cold working processes such as cold heading and cold extrusion to manufacture high-strength fasteners and precision structural components,and is widely applied in mechanical,automotive,and other related industries.
2.Classification of SWRCH35K Steel
Product Form:Mainly available as coiled wire rods(suitable for automated cold heading) and small batches of straight bars(suitable for manual or non-standard processing).
Process State:Annealed state(excellent plasticity,resistant to cracking during cold heading,the mainstream in the market) and hot-rolled state(higher hardness,lower plasticity,requiring secondary annealing).
Performance Grade:Primarily achieves Grade 8.8 after heat treatment,with some high-quality products capable of reaching Grade 10.9.
Customized Types:Includes environmentally friendly low-phosphorus and low-sulfur variants,high-precision controlled-rolled types,and delayed fracture-resistant types tyo meet the demands of high-end industries.
3.Advantages of SWRCH35K Steel
Excellent cold heading formability with low risk of cracking,making it suitable for processing complex components.
Balanced strength and toughness,meeting the requirements for Grade 8.8 and partially Grade 10.9 fasteners.
Low cost and high material utilization,offering outstanding cost-effectiveness.
Produced using killed steel process,ensuring stable quality and easier compliance with industry certifications.
Customizable forms such as coiled wire rods or straight bars to adapt to different production needs.
4.Limitations
Low maximum strength,unable to meet the requirements for Grade 12.9 and higher fasteners.
The bare material is prone to rusting and requires additional anti-corrosion treatment.
Unsuitable for high-temperature,heavy-load,or critical components applications.
Hot-rolled state cannot be used directly for cold heading.Annealing is required and it causes significant die wear.
Poor low-temperature toughness,prone to brittle fracture in extremely cold environments.
5.SWRCH35K Steel Application Scenarios
Automotive Manufacturing:Engine bolts,chassis connectors,fastening,screws
for new energy battery packs,spring seats,and other medium-load components.
Fastener Production:Primarily Grade 8.8 standard bolts,nuts,rivets,and pins,also applicable for some non-critical Grade 10.9 fasteners.
Electronics and Precision Instruments:Micro screws,precision instrument rivets,connector pins,and other small precision parts.
General Machinery and Agricultural Equipment:Bearing housing,couplings,
agricultural machinery parts,and structural connectors for general equipment.
Home Appliance and Furniture Hardware:Self-tapping screws for washing machine/air conditioner casings,furniture assembly bolts,hinge pins,and similar components.
الخاتمة
SWRCH35K is a medium-carbon cold heading quality killed steel defined b=y the JIS standard.It is characterized by excellent cold workability and a balances combination of strength and toughness.In its annealed state,its hardness typically ranges from 72-85HRB.After heat treatment,it can reliably achieve Grade 8.8 strength,with some variants reaching Grade 10.9.
The material is primarily supplied in two forms：Coiled wire rods(mainstream,suitable for automated cold heading) and straight bars(for small-batch manual processing).It is also classified by its processing state:annealed(good plasticity,low cracking tendency) and hot-rolled(requires secondary processing).Customized versions,such as low- phosphorus and low-sulfur grades,are also available.
Its primary application is in manufacturing medium-to high-fasteners for the automotive,machinery,and electronics industries,including components like engine bolts and precision rivets.Key advantages include superior formability,high cost-effectiveness,and consistent quality.Its main limitations are a relatively low maximum strength,susceptibility to rust in its bare state,and unsuitability for high-temperature,heavy-load,or extremely low-temperature operating conditions.
7.FAQ
Is SWRCH35K bare material prone to rusting?
Yes,it is prone to rusting.As it contains no rust–resistance alloying elements,surface treatments such as zinc plating or zinc diffusion coating are required for use in outdoor or humid environments.
Is SWRCH35K suitable for high-temperature or extremely low-temperature applications?
Nor recommended.It’s strength degrades rapidly under high temperatures,while its toughness decreases in low-temperature environments,making it prone to brittle fracture.It is only suitable for moderate-load applications under normal temperature conditions.
What are the main product forms of SWRCH35K?
The primary form is coiled wire rods with diameters ranging from 5.5 to 22mm,which are suitable for large-scale cold heading production.Additionally,straight bars with lengths of 3 to 6 meters are available,catering to small-batch or non-standard processing needs.
