Ika Dewi Wijayanti NIP 2100201301001

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Pengujian Tarik (Tensile Test)

• Ika Dewi Wijayanti

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Latar belakang

• Kebutuhan desain dan perencanaan material di
  dalam sebuah konstruksi
• Tegangan hasil uji tarik (awal terjadinya
  deformasi plastis)?tegangan ijin
  material?dibandingkan dengan tegangan riil yang
  diterima oleh material

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Pengujian
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Spesimen Uji

• JIS Z 2201 (Jepang)
• ASTM E-8 (USA)
• BS (Eropa)

Standard pengujian
Gauge length Daerah yang mengalami efek
pembebanan ? ditentukan berdasarkan standard uji
benda uji
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Fenomena Uji Tarik
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Fenomena Uji Tarik
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Fenomena Uji Tarik
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Fenomena Uji Tarik
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Hasil uji tarik
Transformasi grafik F - ?l ke grafik ? - ?
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Rumus
Modulus Elastisitas (Modulus Youngs)
Poissons Ratio
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Contoh Soal

• From the tensile stressstrain behavior for the
  brass specimen shown in the Figure, determine the
  following
• The modulus of elasticity
• The yield strength at a strain offset of 0.002
• The maximum load that can be sustained by a
  cylindrical specimen having an original diameter
  of 12.8 mm (0.505 in.)
• The change in length of a specimen originally 250
  mm (10 in.) long that is subjected to a tensile
  stress of 345 MPa (50,000 psi)

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Jawaban

• a. The modulus of elasticity is the slope of the
  elastic or initial linear portion of the
  stressstrain curve

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Jawaban

• b. Offset Yield strength

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Jawaban

• c. The maximum load that can be sustained by the
  specimen ? tensile strength point

d. To compute the change in length, it is first
necessary to determine the strain that is
produced by a stress of 345 MPa. This is
accomplished by locating the stress point on the
stressstrain curve, point A, and reading the
corresponding strain from the strain axis, which
is approximately 0.06
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Latihan
Gambar dibawah ini adalah grafik P - ?L hasil uji
tarik suatu batang baja berdiameter 40 mm dan
gauge length 200 mm. Reduction of area 10 .

• Tentukan
• Tensile strength dan offset yield strength
• Kekakuan baja tersebut...
• Modulus ketangguhan dan modulus resilience
• Ductility dalam percentage of elongation
• Tegangan sebenarnya pada saat patah