1045 C45 S45C 1.1191 CK45 Round Steel Bar
Medium carbon engineering bar in 0-500mm diameter hot rolled black or cold drawn bright
Specifications
Round Steel Bar in Engineering and Nitriding Grades
Bar stock for machined shafts pins and tooling where the grade decides whether the part is turned hardened or nitrided
Steel bar covers the solid round sections that machine shops turn, mill and heat treat into shafts, pins, spindles and tool bodies. Two families sit in this range: 1045 C45 S45C 1.1191 CK45 medium carbon engineering steel with good machinability and high tensile properties, and 41CrAlMo7 1.8509 nitriding steel chosen for high strength, wear resistance and toughness in components that run hot or abrasive. CK45 is normally supplied as plate, round bar, flat bar, square bar, hexagonal bar and pipe, with hot rolled black surface or cold drawn bright surface, and larger sections handled as forgings. The sourcing problem is grade naming: the same medium carbon steel appears on drawings as 1045, C45, S45C, 1.1191 and CK45, and a buyer who treats those as five separate materials ends up with five separate inquiries.
Full Range
All 2 Products in Steel Bar
Bar stock for machined shafts pins and tooling where the grade decides whether the part is turned hardened or nitrided
41CrAlMo7 1.8509 Round Steel Bar
Nitrogen hardening chromium aluminium molybdenum bar from 5mm to 500mm diameter
SpecificationsProblems Solved
What This Range Is For
One Steel Written Five Ways
1045, C45, S45C, 1.1191 and CK45 all describe the same medium carbon engineering steel. Quoting against whichever designation the drawing carries removes a round of clarification before the bar is even priced.
Machining Allowance Bought Twice
Buying hot rolled black bar for a part that needs a bright finished diameter means paying for metal that goes into the swarf bin. Cold drawn bright surface reduces the cleanup cut when the finished diameter is close to stock.
Wear Parts Distorting on Through Hardening
Through hardened components move and then need regrinding. 41CrAlMo7 1.8509 is a nitrogen hardening steel, so the hard case is produced without the quench cycle that distorts a finished shaft.
Heat Softening Shafts and Spindles
Components running at raised working temperature lose hardness and start to gall. 41CrAlMo7 1.8509 is used for durable and heat resistant components and holds up where a plain carbon bar cannot.
Large Diameters Not Available As Rolled Bar
Heavy sections rolled from bar stock can leave a poor core. For large sizes forging is the better route and is handled here rather than pushing the job onto an unsuitable rolled section.
Who Buys It
Buyers Who Order From This Range
- Machine shops turning shafts, pins and bushings from 1045 C45 S45C bar
- Gearbox and drive component makers needing a medium carbon steel with high tensile properties
- Extruder and injection molding screw manufacturers specifying 41CrAlMo7 1.8509 for nitriding
- Tooling and die shops buying bar for holders, bolsters and wear inserts
- Agricultural and construction equipment builders replacing worn shafts and linkage pins
- Distributors supplying engineering steel bar to regional maintenance workshops
Core Advantages
Why Source This Range From Tianyu Metal
Two Grade Families Covering Turn and Nitride Work
The medium carbon range handles general engineering structural parts while 41CrAlMo7 1.8509 covers components that must be surface hardened without a distorting quench, so one supplier serves both routes.
Machinability Stated Not Assumed
1045 C45 S45C 1.1191 CK45 is described as having good machinability and high tensile properties, which is why it remains the default choice for parts that are cut before they are heat treated.
Black or Bright Surface on Request
Hot rolled black surface for parts that will be machined all over, cold drawn bright surface where the as delivered diameter is close to the finished size.
More Than Round Bar From the Same Grade
CK45 is normally supplied as plate, round bar, flat bar, square bar, hexagonal bar and pipe, so a job needing several forms of the same steel does not fragment across suppliers.
Forging Route for Heavy Sections
Large sizes are better produced as forgings, which keeps the core sound in sections where a rolled bar would be the weaker option.
Hardenability for Severe Duty
The chemical composition of 41CrAlMo7 1.8509 gives excellent hardenability, which is what makes it suitable for components working under extreme conditions.
Application Scenarios
Where This Range Ends Up
Shafts Spindles and Axles
Turned and keyed drive components in 1045 C45 where tensile strength and clean machining matter more than surface hardness.
Extrusion and Injection Screws
Screw and barrel components in 41CrAlMo7 1.8509 that are nitrided to resist wear from filled polymer and abrasive compound.
Linkage Pins and Bushings
Replacement pins and bushings on loaders, harvesters and material handling equipment where the original part has worn oval.
Tool Holders and Die Components
Bolsters, ejector parts and holders machined from medium carbon bar and then hardened only where the wear face demands it.
Hydraulic and Mechanical Rods
Rods and stems turned from cold drawn bright bar so the finished diameter needs a light cut rather than a full skim.
Hot Working Equipment Parts
Components on presses, furnaces and processing lines where the nitriding grade is chosen for heat resistance and toughness together.
Buying Guide
What To State When You Order
State the grade in the designation your drawing uses, such as 1045, C45, S45C, 1.1191, CK45 or 41CrAlMo7 1.8509
Give the diameter and the cut length, and say whether lengths must be equal or a mill length is acceptable
Say whether you want hot rolled black surface or cold drawn bright surface, and how much machining allowance you expect
Confirm the delivery condition you need and whether the bar will be nitrided, hardened or used as supplied
Tell us if a form other than round bar is wanted, since flat, square and hexagonal bar and pipe are available in this steel
Ask for the mill test certificate and state any end marking or bundling your goods inward check requires
Related
Industries and Solutions Around Steel Bar
Tooling and Mould Making
A tool room loses more time waiting for a block than cutting one. Tianyu Metal stocks the four families a die shop actually orders
Read more
Construction Machinery and Agriculture
One loader or one tractor needs four different steels and most fabrication shops buy them from four different suppliers. The struc
Read more
Automotive and Transport
Vehicle and trailer components fail on fatigue, not on a single overload, so the grade behind each part matters more than the pric
Read more
Grade Selection and Substitution
A purchasing engineer rarely gets a free choice of grade. The drawing names one designation, the material that is actually availab
Read more
Cut to Size and Processing
Buying full plates to make small panels means paying freight on offcuts and storing them afterwards. Tianyu Metal processes steel
Read more
Inspection and Mill Test Certificates
Material without paperwork cannot be released into a job, however good the steel is. A quality department that receives plate with
Read moreQuestions Buyers Ask
Steel Bar FAQ
Are 1045 C45 S45C 1.1191 and CK45 the same steel?
They are the designations used in different standards for the same medium carbon engineering structural steel. Order against whichever one appears on your drawing and the material will be supplied and certified to it.
Why choose 41CrAlMo7 1.8509 over a through hardening grade?
41CrAlMo7 1.8509 is a nitrogen hardening steel known for high strength, wear resistance and toughness. The hard surface is developed by nitriding, so a finished component keeps its dimensions instead of moving in a quench.
What surface conditions are available?
Hot rolled black surface and cold drawn bright surface are both normal. Bright bar suits parts machined close to the delivered diameter, black bar suits parts that are machined all over anyway.
Can you supply shapes other than round bar in these grades?
Yes. The medium carbon grade is normally supplied as plate, round bar, flat bar, square bar, hexagonal bar and pipe, so flats and hexagons can go on the same order as the rounds.
What do you recommend for very large diameters?
For large sizes forging is the better option. Send the finished component dimensions and we will confirm whether a rolled bar or a forged blank suits the part.
Do you supply the bar cut to our lengths?
Yes. Send the cutting list with diameters and lengths so the bar arrives ready to load into the machine rather than needing a saw shop first.
Get a Quotation on Steel Bar
Tell us state the grade in the designation your drawing uses, such as 1045, C45, S45C, 1.1191, CK45 or 41CrAlMo7 1.8509 and we will come back with price, availability and what the mill test certificate will show for steel bar.