Martensitic Stainless 440C 51400 Series Thrust Ball Bearings
Grade, hardness, corrosion behavior, service temperature and the full bore range for this material.
Martensitic Stainless 440C 51400 Series Thrust Ball Bearings are made from AISI 440C = X105CrMo17 (1.4125), hardened and tempered — the only common stainless hard enough to form a rolling raceway. Corrosion behavior: good in water, steam, mild chemicals and food service; it is a hardenable stainless, so it holds less chromium in solution than 304 and will stain in standing chlorides. The material is magnetic, and the usable service range is about -30 °C to +180 °C in ordinary bearing service, the lubricant usually deciding before the steel does. In practice this material is the standard corrosion-resistant bearing steel; a stainless bearing is rated below the same envelope in GCr15, so take its load ratings from the stainless table and never from the chrome steel one.
Material
AISI 440C = X105CrMo17 (1.4125), hardened and tempered — the only common stainless hard enough to form a rolling raceway
Corrosion resistance
Good in water, steam, mild chemicals and food service; it is a hardenable stainless, so it holds less chromium in solution than 304 and will stain in standing chlorides
Magnetic response
Magnetic
Service temperature
about -30 °C to +180 °C in ordinary bearing service, the lubricant usually deciding before the steel does
Property figures are typical for the material. In an assembled bearing the lubricant, the seals and the cage frequently reach their limits before the material does, so check all four against the duty. Material certification is available on request for production orders.
Martensitic Stainless 440C 51400 Series Thrust Ball Bearings are dimensioned to ISO 104 / DIN 711 / GB/T 301 exactly as the standard version is: the material changes the properties, never the envelope. What it does change — good in water, steam, mild chemicals and food service; it is a hardenable stainless, so it holds less chromium in solution than 304 and will stain in standing chlorides, magnetic and the service range about -30 °C to +180 °C in ordinary bearing service, the lubricant usually deciding before the steel does — is set out below with the full size chart.
Why Martensitic Stainless 440C for 51400 Series Thrust Ball Bearings
The standard corrosion-resistant bearing steel; a stainless bearing is rated below the same envelope in GCr15, so take its load ratings from the stainless table and never from the chrome steel one. In a 51400 series thrust ball bearings it is the ring and rolling element steel of the corrosion-resistant version.
It is the compromise that makes a corrosion-resistant rolling bearing possible: enough carbon to be hardened to a raceway hardness, enough chromium to resist water and mild chemicals. Everything else about the bearing — the envelope, the tolerance class, the clearance group — is unchanged.
Material Properties
Grade designation
AISI 440C = X105CrMo17 (1.4125), hardened and tempered — the only common stainless hard enough to form a rolling raceway
Magnetic response
Magnetic
Service temperature
About -30 °C to +180 °C in ordinary bearing service, the lubricant usually deciding before the steel does
Corrosion characteristic
Good in water, steam, mild chemicals and food service; it is a hardenable stainless, so it holds less chromium in solution than 304 and will stain in standing chlorides
Alternatives and When to Switch
If the load matters more than the corrosion, go back to GCr15 with the right seals and a corrosion-inhibiting grease — a sealed chrome steel bearing outlasts a stainless one in many "wet" applications that are only occasionally wet. If the corrosion matters more than the load, go past stainless: a full ceramic or a polymer-housed bearing does not corrode at all.
What the Material Changes About the Bearing
The envelope is unchanged and the bearing drops into the same seat, but the load ratings are not the chrome steel ratings and must not be carried across. Expect a lower rating, a slightly lower temperature ceiling, and — in exchange — a bearing that survives the wash, the condensation or the food process that would rust a standard one.
Sizes of 51400 Series Thrust Ball Bearings Available in Martensitic Stainless 440C
Designation
Bore d (mm)
Outer diameter D (mm)
Height H (mm)
Chamfer r min (mm)
51405
25
60
24
1
51406
30
70
28
1
51407
35
80
32
1.1
51408
40
90
36
1.1
51409
45
100
39
1.1
51410
50
110
43
1.5
51411
55
120
48
1.5
51412
60
130
51
1.5
51413
65
140
56
2
51414
70
150
60
2
51415
75
160
65
2
51416
80
170
68
2.1
51417
85
180
72
2.1
51418
90
190
77
2.1
51420
100
210
85
3
Other ways to specify the 51400 Series Thrust Ball Bearings
Customize the parameters below — every spec field is editable, and the drawing redraws to match the values you choose. Changing the designation snaps the other fields to that size's standard values; you can then override any individual value.
Sends the selected values to the quote form below.
Our facility
Held in production, not just on paper
The tolerances above are decided on the grinding and superfinishing lines in our own plant, and gauged on every ring rather than on a sample. A dimension is only worth quoting if it survives the process that produces it.
Request a Quote
The form below follows the current technical drawing configuration. Change the drawing values above and the request details update automatically.
Dimensions & Specifications (ISO 104 / DIN 711 / GB/T 301)
Designation
Bore d (mm)
Outer diameter D (mm)
Height H (mm)
Chamfer r min (mm)
51405
25
60
24
1
51406
30
70
28
1
51407
35
80
32
1.1
51408
40
90
36
1.1
51409
45
100
39
1.1
51410
50
110
43
1.5
51411
55
120
48
1.5
51412
60
130
51
1.5
51413
65
140
56
2
51414
70
150
60
2
51415
75
160
65
2
51416
80
170
68
2.1
51417
85
180
72
2.1
51418
90
190
77
2.1
51420
100
210
85
3
Video: Martensitic Stainless 440C 51400 Series Thrust Ball Bearings
Third-party video, selected automatically for this topic. It is not produced by Bushing Bearings and is not a specification source — use the tables on this page for dimensional data.
Frequently Asked Questions
Are Martensitic Stainless 440C 51400 Series Thrust Ball Bearings magnetic?
Martensitic Stainless 440C is magnetic.
What temperature can Martensitic Stainless 440C 51400 Series Thrust Ball Bearings run at?
The usable range for the material is about -30 °C to +180 °C in ordinary bearing service, the lubricant usually deciding before the steel does. In an assembled bearing the lubricant, the seals and the cage frequently give out before the material does, so check all four against the duty.
What corrosion resistance does Martensitic Stainless 440C give?
Corrosion behavior: good in water, steam, mild chemicals and food service; it is a hardenable stainless, so it holds less chromium in solution than 304 and will stain in standing chlorides.
Why is Martensitic Stainless 440C used for this part?
It is the compromise that makes a corrosion-resistant rolling bearing possible: enough carbon to be hardened to a raceway hardness, enough chromium to resist water and mild chemicals. Everything else about the bearing — the envelope, the tolerance class, the clearance group — is unchanged.
How do I request a quotation?
Use the technical drawing on this page to pick the exact configuration, then submit it with the quote form. We respond within one business day.
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