Intermediate Transformation Products

横笛吹雨

STANDARD FOR CASE HARDENED HEAT TREATED COMPONENTS---RES10410
...................
Intermediate transformation products at the surface are unacceptable except as described in the "Surface Structure" section above. Special print notations may also indicate acceptance of surface intermediate transformation products as shown in the example below.
HT 10T
RC 56 MINIMUM EXCEPT MAY BE
RC 50 MINIMUM IN THE ROOT
This note implies that intermediate products are permitted at the surface of the gear root.
The visual estimated depth to 5% intermediate products should be, at a minimum, 50% of the effective case measurement on a gear pitch line or shaft diameter.
For gear roots, the visual estimated depth to 5% intermediate products should be, at a minimum, 25% of the effective case depth measurement of the gear root

How to translate the details overstriking above accurately? especially"5%-50%"and"5%-25%"?

[ 本帖最后由 WJFU66 于 2009-4-11 12:18 编辑 ]

横笛吹雨

Help me,please

陆丰

Intermediate transformation products at the surface are unacceptable or acceptance.
I want to know what are the Intermediate transformation products?

横笛吹雨

I do not know,too. Pristine print has not definition.May be troostite or not-Matensite?

[ 本帖最后由 WJFU66 于 2009-4-11 12:49 编辑 ]

hlqhlq

Let me take an example: the ECD(有效层深度) of pitch is 0.8mm, so the depth of 5%ITP of pitch must exceed 0.4mm(0.8x50%);the ECD of root is 0.5mm,so the depth of 5%ITP of root must exceed 0.125mm(0.5x25%).

横笛吹雨

Because“Intermediate transformation products at the surface are unacceptable except”，why"exceed"?I think it should be lower than ......

陆丰

when you measure on a gear pitch line or shaft diameter at 50% of the effective case ,the visual estimated depth of the intermediate products should be to 5% ,at a minimum.
When you make a measure on the gear root at 25% of the effective case depth ,the visual estimated depth of the intermediate products should be to 5%  at a minimum.

横笛吹雨

Thanks,I see.
Now,If the visual estimated depth to 5% intermediate products is 51% of the
effective case measurement on a gear pitch line or shaft diameter,would it can be acceptable?

横笛吹雨

Oh,I am an apple-head,I make the wrong side out.
Thank you,陆丰and hlqhlq

陆丰

I wonder whether it is acceptable, it should be based on the experiment.

横笛吹雨

My "51%" is only instance,but according to the standard,it should be acceptable.
Once I have mistaken the visual estimated depth to 5% intermediate products for the more shoal the more better,and so ,make the wrong side out

横笛吹雨

I have searched the definition of" Intermediate transformation products"-----------
Microstructural characteristic obtained during quenching which indicates incomplete martensitic transformation. Typically, the structure resembles bainite and/or pearlite. Frequently referred to as secondary transformation products.