A Six-sigma approach for benchmarking of RP&M processes

  • M. Mahesh
  • Y. S. Wong
  • J. Y. H. Fuh
  • H. T. Loh
ORIGINAL ARTICLE

Abstract

This paper presents a methodology of using six-sigma quality tools for benchmarking of rapid prototyping & manufacturing (RP&M) processes. It involves the fabrication of a geometric benchmark part and a methodology to control and identify the best performance of the process to reduce the variablity in the fabricated parts. The approach is demonstrated with a case study based on the direct laser sintering (DLS) process for prototyping using plastic powder. In the case study an identified set of six-sigma/ statistical process control tools is employed to determine and best tune factors affecting the desired outcomes of the built parts.

Keywords

Benchmarking Decision support Process characterization Process optimization Six-sigma 

Abbreviations

GBP

Geometric benchmark part

MBP

Mechanical benchmark part

BL

Blend

CF

Chamfer

CB

Cube

CN

Cones

CH

Cylindrical holes

FB

Flat beam

FL

Fillet

FF

Free-form features

HC

Hollow cylinders

HS

Hollow squares

SB

Square base

SC

Solid cylinders

SH

Small holes

SL

Slots

SP

Spheres

TC

Thin cylinders

TS

Thin slots

TW

Thin walls

RP&M quality characteristics GA

Geometric accuracy (deviation measured in mm)

SR

Surface roughness, Ra in μm

Control factors: LP

Laser Power in W

LT

Layer thickness in mm

PBT

Part bed temperature in ° C

SS

Scan speed in mm/s

Compensations:L

linear dimension (length, breadth or height in mm)

La

actual design dimension of STL file in mm

Lm

measured dimension on fabricated GBP in mm

k

scaling factor

b

laser beam offset factor in mm

s

shrinkage in mm

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Copyright information

© Springer-Verlag London Limited 2006

Authors and Affiliations

  • M. Mahesh
    • 1
  • Y. S. Wong
    • 1
  • J. Y. H. Fuh
    • 1
  • H. T. Loh
    • 1
  1. 1.Department of Mechanical EngineeringNational University of SingaporeSingaporeSingapore

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