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Need glass-like surface on 1144 "stress-proof" steel

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I want to machine a surface in 1144 stress proof material after I machine it I want to burnish or smooth the machined surface to a glass like condition. Any suggestions to the tooling required.

Kelly Weener
metal component parts - Hudsonville, Michigan, USA

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First of three simultaneous responses -- +++

Impossible to recommend anything if we do not know size, geometry, quantity and cost scenario for your application.

Guillermo Marrufo
Monterrey, NL, Mexico

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Second of three simultaneous responses -- +++

Roller burnishing is fairly common, and can be performed using CNC mills and lathes. Go to the Cogsdill for more information. Electropolishing is the standard treatment used for obtaining smooth surfaces on metal components, with the best typically around 2-5 microinches. Metal Improvement has a finish they call CASE (Chemical Assisted Surface Engineering) that is a two-step shot-peening/chemical finish that can obtain Ra < 10 microinches. REM Chemicals offers their Isotropic Finish process which they claim has Ra as low as 1 microinch.

Toby Padfield
Automotive module supplier - Michigan

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Third of three simultaneous responses -- +++

I think you will have to clarify your question. Glass like is pretty vague. Are you talking about a reflective finish or a smooth finish? They are not exactly the same. Also, what about flatness?

AF Kenton Huntingdon Valley, Pennsylvania

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Kelly, something else you need to realize is that 1144 is a free machining steel, meaning it is full of manganese sulfides to enhance chip breaking during machining. These don't polish well. If you seek a mirror finish, you'll be disappointed, as the best surface you'll get will show what look like small pits.

That said, I think you're best off pursuing the roller burnishing option. Good luck!

Lee Gearhart metallurgist East Aurora, New York