Material specification page for phillips oval countersunk head machine screws, metric in Property Class 12.9 Steel. Covers the grade designation (ISO 898-1 property class 12.9), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to ISO 7047.
Why Choose Property Class 12.9 Steel for Phillips Oval Countersunk Head Machine Screws, Metric
The highest common strength class, for high-load machine assembly. For phillips oval countersunk head machine screws, metric, this matters when requires plating or black-oxide protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 898-1 property class 12.9 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | commonly limited to approx. +300 °C; confirm against the coating and the load |
| Corrosion characteristic | Requires plating or black-oxide protection |
Corrosion Behavior in Service
Carbon and alloy steel phillips oval countersunk head machine screws, metric require a coating for corrosion protection. Zinc plating (with or without passivation) is the most common; hot-dip galvanizing is used for outdoor structural service; black-oxide is mainly a tarnish-prevention finish for tool-room use.
Comparable Grades
For Phillips Oval Countersunk Head Machine Screws, Metric, class 8.8 is the comparable strength step. Move up when the joint preload approaches the proof load of the current class; move down when the joint is over-specified. For corrosion-critical service, switch to stainless A2 or A4.
Sizes of Phillips Oval Countersunk Head Machine Screws, Metric Available in Property Class 12.9 Steel
| Size | Pitch P (mm) | a (mm) | b (mm) | Head diameter dk (mm) | csh_diam (mm) | csh_height (mm) | n_min (mm) | r (mm) | t_mean (mm) | x (mm) | Length range l (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M1.6 | 0.35 | 0.7 | 25 | 3.6 | 2.8 | 1.0 | 0.46 | 0.2 | 0.4 | 0.9 | 3~16 | ISO 7047 |
| M2 | 0.4 | 0.8 | 25 | 4.4 | 3.6 | 1.2 | 0.56 | 0.3 | 0.5 | 1.0 | 3~20 | ISO 7047 |
| M2.5 | 0.45 | 0.9 | 25 | 5.5 | 4.5 | 1.5 | 0.66 | 0.3 | 0.6 | 1.1 | 3~25 | ISO 7047 |
| M3 | 0.5 | 1.0 | 25 | 6.3 | 5.3 | 1.65 | 0.86 | 0.4 | 0.7 | 1.25 | 4~30 | ISO 7047 |
| (M3.5) | 0.6 | 1.2 | 38 | 8.2 | 7.1 | 2.35 | 1.06 | 0.4 | 1.0 | 1.5 | 5~35 | ISO 7047 |
| M4 | 0.7 | 1.4 | 38 | 9.4 | 8.2 | 2.7 | 1.26 | 0.5 | 1.1 | 1.75 | 5~40 | ISO 7047 |
| M5 | 0.8 | 1.6 | 38 | 10.4 | 9.2 | 2.7 | 1.26 | 0.6 | 1.2 | 2.0 | 6~45 | ISO 7047 |
| M6 | 1.0 | 2.0 | 38 | 12.6 | 11.2 | 3.3 | 1.66 | 0.7 | 1.4 | 2.5 | 8~60 | ISO 7047 |
| M8 | 1.25 | 2.5 | 38 | 17.3 | 15.6 | 4.65 | 2.06 | 1.0 | 2.0 | 3.2 | 10~60 | ISO 7047 |
| M10 | 1.5 | 3.0 | 38 | 20.0 | 18.1 | 5.0 | 2.56 | 1.2 | 2.3 | 3.8 | 12~60 | ISO 7047 |
Dimensions are independent of the material: every size above is available in Property Class 12.9 Steel.
Custom manufacturing · Made to drawing
Need this screw in a grade that is not listed?
Grade 12 9 Steel is one of the grades the catalog describes. Where the standard stops, the drawing takes over: fine pitches, left-hand threads, partial threading, and property classes above the catalogued grade where material and heat treatment allow. Made by cold heading or warm forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
