cold shut and misrun defect in al casting
TRANSCRIPT
Cold Shut / Misrun defect in Alumunium Casting
Rudiyansah
0806331973
Teknik Metalurgi dan Material
Universitas Indonesia
Misrun/ Cold Shut
Misruns merupakan suatu cacat yang terjadi karena logam cair tidak mengisi seluruh rongga cetakan sehingga benda cor menjadi tidak lengkap atau ada bagian yang hilang
Misrun defect
Example of misrun defect
Cold Shut and Misrun
• Probable Cause
a. Poor poring practice
b. Improper gating
c. Low shell permeability
d. Low metal fluidity
e. Low metal or mold temperature
f. Ketidakseragaman dimensi benda cor, mengganggu aliran dari logam cair
g. Lubang angin yang kurang pada cetakan
h. Coating terlalu tipis
i. ukuran,penempatan dan distribusi saluran masuk, runner dan sprue tidak sesuai
Cold Shut and Misrun
• Suggested Cure
a. Increas metal and/or mold temperature
b. Increase head pressure and/or rate of pour; avoid splashing
c. improve gating to enhance mold fill
d. Modify alloy composition to enhance fluidity
e. Increase permeability by using coarse refractory flour (200 mesh for primary, 120 mesh for backups)
f. Insulates the mold or use an insulating refractory (Alumina bubbles)
g. lubang angin (ventilasi) harus ditambah
Comparison of filling sequences, with and without misrun, in Alumunium Motor Rotor in Die casting
• Numerical analysis result without misrun (Core length 700mm, slot width 9mm, slot length 25.5mm)
Comparison of filling sequences, with and without misrun, in Alumunium Motor Rotor in Die casting
• Numerical analysis result with misrun (Core length 700mm, slot width 7.6mm, slot length 18.8mm)
Misrun defect in Alumunium motor rotor (Hyundai Heavy Industries)
Misrun defect in Alumunium motor rotor (Hyundai Heavy Industries)
Surface defect of semi-solid die casting of ADC 12 Alumunium alloy
Misrun defect in intercooler of radiator assembly, which is used in buses and trucks
Continued (Prevention)
• To minimize the misrun defect in intercooler assembly, several parameter process must be kept in controlled. Such as :
Fluid flow behaviour, gating and feeding design, flows breaks between riser and casting, hot spot area
Continued (prevention)
Actualization of intercoolar assembly condition with gating system and risers
Continued (prevention)
• Simulation with ProCAST, to predict fluid flow behaviour in casting process
Continued (prevention)
• Problems that occurred and must be evaluate to minimize the misrun
Continued (prevention)
Continued (prevention)
Continued (prevention)
Continued (prevention)
Safe band for operating DIE, in intercooler assembly process
ReferencesBambang Suharno.Diktat kuliah Pembentukan Logam.FTUI
http://www.foundryinfo-india.org/tech_section/pdf/15_OP.pdf
http://www.me.gatech.edu/jonathan.colton/me4210/castdefect.pdf
http://www.foseco.com.tr/tr/downloads/FoundryPractice/235-03_Using_the_SEM_for_defect_analysis.pdf
http://www.indianfoundry.org/docs/paper_4_jan11.pdf
http://www.springerlink.com/content/pmc0lej1fw6xc9wl/
http://www.ysxbcn.com/upfile/soft/201099/33-p1756-4163.pdf
http://www.wpi.edu/Pubs/ETD/Available/etd-1223102-102625/unrestricted/ziolkowski.pdf
http://www.ifme.eu/scopi/group/foundry/foundry.nsf/pagesref/SBDD-7MDMSB?Opendocument&lang=en