LAPORAN 06-1

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LABORATORIUM PENGUJIAN BAHAN

Kelompok 06

Latar Belakang Pengujian

BAB I

LATAR BELAKANG PENGUJIAN

Seperti kita ketahui bahwa dalam bidang industri permesinan tidak terlepas dari

ilmu logam terutama menyangkut masalah – masalah yang ada hubungannya dengan

pemilihan kualitas bahan, cara – cara pengerjaannya, dan untuk penekanan biaya

produksi.

Percobaan yang dilakukan di Laboratorium Pengujian Bahan Fakultas Teknik

ni!ersitas Brawijaya, merupakan salah satu inspeksi untuk mengetahui kualitas logam,

hal ini perlu sekali karena berkaitan dengan produk yang akan dihasilkan. Sebelum

memproduksi suatu bahan kita harus mengetahui spesi"ikasi bahan tersebut. #engan

demikian kita akan mengetahui langkah apa yang perlu diambil dalam proses

pengerjaan dan sekaligus dapat kita ketahui bahan yang kita gunakan memenuhi syarat

untuk produk yang telah ditargetkan baik mutu maupun dimensinya.

#engan mengetahui spesi"ikasi bahan, langkah – langkah proses pengerjaan dan

mutu yang ditargetkan akan mencapai hasil yang tepat. #ari sini biaya produksi dapat

dipilih, tentunya digunakan biaya yang paling murah. $adi, apabila kita ingin

memproduksi suatu bahan yang berkualitas baik, maka kita harus mengetahui

spesi"ikasi bahan yang digunakan. Spesi"ikasi suatu bahan dapat diketahui dengan

melakukan pengujian – pengujian yang kita lakukan di laboratorium. %leh karena itu

dilakukan pengujian untuk mengetahui si"at mekanik suatu material di Laboratorium

Pengujian Bahan Fakultas Teknik ni!ersitas Brawijaya.

&

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Kelompok 06 Pengujian Kekerasan dan Mikrostruktur

BAB II

PENGUJIAN KEKERASAN DAN MIKROSTRUKTUR

2.1 Tujuan Pengujian

&. 'engetahui angka kekerasan suatu bahan.

(. 'engetahui pengaruh perlakuan panas terhadap kekerasan bahan.

). 'engetahui salah satu cara pengukuran kekerasan.

*. 'engetahui perubahan struktur pada setiap perlakuan.

2.2 Definisi Kekeasan

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2.! Pe"aksanaan Pengujian

(.).& A"a# $an Ba%an &ang Digunakan

ntuk ji +ekerasan

1. Rockwell Type Hardness Tester

#igunakan untuk mengukur kekerasan pada spesimen.

'erk - /001

2ndentor bola 3ockwell &4&/5

2ndentor intan &(0

Buatan $erman

Skala pembebanan 631 7 899 :

63B 7 ;90 :

63- 7 &*

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=ambar (.& Rockwell Type Hardness Test Sumber Laboratorium Pengujian Bahan Teknik 'esin Fakultas Teknik ni!ersitas

Brawijaya >(0&/?

2. Centrifugal Sand Paper Machine

#igunakan untuk menghaluskan benda kerja.

'erk S1P623 ))0

Buatan $erman

#iameter &8 cm

Putaran &(0 rpm

#aya 0.88 k@

Tegangan ((0

=ambar (.( Centrifugal Sand Paper Machine

Sumber Laboratorium Pengujian Bahan Teknik 'esin Fakultas Teknik ni!ersitas

Brawijaya >(0&/?

). #apur Listrik

)

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#apur ini digunakan untuk proses pemanasan >heating ?, penahanan

>holding ?, dan pendinginan >cooling ? dalam dapur.

Spesi"ikasi dapur listrik yang digunakan adalah

'erk %PA:B1 6%F'1::

Tipe A 4 ;0

oltage ((0 !olt

#aya ),) k@

Suhu ma &&00o-

Buatan 1ustria

=ambar (.) #apur Listrik


Brawijaya >(0&/?

*. Tang penjepit

#igunakan untuk mengambil benda uji dari dapur listrik pada proses

perlakuan panas.

=ambar (.* Tang Penjepit

Sumber Laboratorium Pengujian Bahan Teknik 'esin Fakultas Teknik ni!ersitasBrawijaya >(0&/?

*

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8. Bak pendingin

#igunakan sebagai tempat media pendingin spesimen pada perlakuan panas

6. Stopwatch

#igunakan untuk mengukur waktu holding

=ambar (./ Stopwatch


Brawijaya >(0&/?

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=ambar (.9 $angka Sorong


Brawijaya >(0&/?

;. Penggaris

#igunakan untuk mengukur dimensi spesimen

=ambar (.; Penggaris


Brawijaya >(0&/?

ntuk 'ikrostruktur

&. 'ikroskop Logam

#igunakan untuk melihat mikrostruktur specimen, #alam pengujian ini

digunakan pembesaran *80 kali.

Spesi"ikasi mikroskop logam yang digunakan

'erk :ikon

Buatan $epang

/

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=ambar (.&0 'ikroskop Logam


Brawijaya >(0&/?

(. +amera

). Atsa

#igunakan untuk memperjelas penampakan struktur mikro spesimen. Atsa

berupa cairan kimia yang akan bereaksi dengan atom tertentu pada logam,

terutama atom – atom yang tidak stabil, misalnya atom pada batas butir. Atsa

yang digunakan pada pengujian ini adalah nital, yang merupakan campuran & – 8

ml white nitric acid dalam &00 ml ethyl 4 ethyl alcohol ;8 – &00 C. :ital akan

menggelapkan perlit, menampakkan batas butir cementite.

=ambar (.&& Atsa


Brawijaya >(0&/?

*. Metal polish

#igunakan untuk menghaluskan dan mengkilapkan permukaan spesimen.

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=ambar (.&( Metal Polish


Brawijaya >(0&/?

;. +ain "lanel

#igunakan untuk menghaluskan dan membersihkan spesimen dari etal

polish yang tersisa.

=ambar (.&) +ain Flanel


Brawijaya >(0&/?

• +omposisi +imia Spesimen

- Spesimen Bohler Special +

- +omposisi - 7 ( C

'n 7 0,) C Si 7 0,( C

-r 7 &( C

9

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• Pergeseran Titik !utectoid

Tabel (.& +omposisi +imia

Sumber #okumentasi Pribadi >(0&/?

&0&0 cm

=ambar (.&* =ra"ik Pegeseran Titik !utectoid


• Bentuk dan #imensi Spesimen

>L1'P231:?

;

:onsur

Paduan

+omposisi

>C?Suhu !utectoid C -

& - (

( 'n 0.)

) Si 0.(

* -r &(

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2.!.2 P'se$u Pengujian

ji +ekerasan

&. Permukaan benda uji dibersihkan dari kotoran dan terak dengan kertas gosok.

(. Spesimen dipanaskan dan diDholding dengan suhu dan waktu tertentu.

). Spesimen dipindahkan dari dapur listrik ke bak pendingin untuk proses

pendinginan pada media tertentu

*. Siapkan permukaan benda kerja

a. 3atakan kedua permukaan benda kerja menggunakan amplas kasar, sehingga

kedua bidang permukaan tersebut sejajar.

b. 6aluskan permukaan benda kerja menggunakan centrifugal sand paper

achine sampai betul – betul rata dan halus dan siap diuji.

8. Siapkan perangkat uji kekerasan 3ockwell - pada ni!ersal 6ardness Tester

a. 'emasang bandul beban >&*

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). Permukaan spesimen yang sudah mengkilap dibersihkan dengan alkohol,

kemudian ditetesi cairan etsa.

*. Spesimen diletakkan pada mikroskop logam, kemudian "okus diatur sampai

didapatkan gambar yang jelas dengan pembesaran *80 kali.

8. #ilakukan pemotretan dengan kamera, kemudian hasilnya dicetak.

2.( Peng'"a%an Da#a

2.(.1 Ana"isa Mik's#uk#u

• 'ikrostruktur Tanpa Perlakuan Panas

+ertas Foto

&0 * cm

=ambar (.&8 'ikrostruktur 'aterial Tanpa Perlakuan


Brawijaya >(0&/?

#ari hasil "oto mikrostruktur tersebut diambil sepuluh sampel untuk

dihitung presentase warna hitam dan putih.

Tabel (.& 'ikrostruktur 'aterial Tanpa Perlakuan

& ( ) * 8

/ < 9 ; &0


#ari sepuluh sampel tersebut dapat diperoleh data sebagai berikut

Tabel (.( Presentase Putih D 6itam :o. Putih >C? 6itam >C?

&&

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&.

(.

).

*.

8.

/.(0&/?

Proporsi dari sampel >p&?

n& 7 &0 &00 7 &000

p& 7 7 .7

standar de!iasi sampel >G&?

H& 7 & D p& 7 & D .. 7

G& 7 7..7

#ari tabel distribusi standar dengan I 7 8C maka diperoleh nilai J>I4(? 7 K

inter!al penduga rataDrata proporsi warna putih

p& – J>I4(?.G& p p& M J>I4(?. G&.........................................................................................................................................

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$adi proporsi warna putih untuk "oto mikrostruktur logam tanpa perlakuan

panas berkisar antara . sampai . dengan tingkat keyakinan ;8C

• 'ikrostruktur dengan Perlakuan Panas

+ertas Foto

&0 * cm

=ambar (.&/ 'ikrostruktur 'aterial dengan Perlakuan

&(

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Brawijaya >(0&/?

#ari hasil "oto mikrostruktur tersebut diambil sepuluh sampel untuk

dihitung presentase warna hitam dan putih.

Tabel (.) 'ikrostruktur 'aterial dengan Perlakuan

& ( ) * 8

/ < 9 ; &0


#ari sepuluh sampel tersebut dapat diperoleh data sebagai berikut

Tabel (.( Presentase Putih D 6itam

:o. Putih >C? 6itam >C?

&.

(.

).

*.

8.

/.(0&/?

Proporsi dari sampel >p&?

n& 7 &0 &00 7 &000

p& 7 7 .7standar de!iasi sampel >G&?

&)

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H& 7 & D p& 7 & D .. 7

G& 7 7..7

#ari tabel distribusi standar dengan I 7 8C maka diperoleh nilai J>I4(? 7 K

.. inter!al penduga rataDrata proporsi warna putih

p& – J>I4(?.G& p p& M J>I4(?. G&

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$adi proporsi warna putih untuk "oto mikrostruktur logam tanpa perlakuan

panas berkisar antara . sampai .. dengan tingkat keyakinan ;8C• ji Beda #ua Proporsi

ntuk mengetahui perbedaan antara proporsi warna putih spesimen tanpa

perlakuan panas dan spesimen dengan perlakuan panas dilakukan pengujian dua

proporsi

6ipotesa 60 p& 7 p(6& p& N p(

#ata untuk menghitung Jhitungn&7&000 p&7 H&7

n(7&000 p(7 H(7 perhitungan Jhitung

Jhitung 7 7

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+edudukan Jhitung pada kur!a normal adalah sebagai berikut

&*

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'ilimeter Block

8 &( cm

=ra"ik (.& +ur!a uji J


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2.(.2 Da#a Ke"')*'k

• #ata Spesimen Tanpa Perlakuan Panas

Tabel (.8 #ata Spesimen Tanpa Perlakuan

:o O O – Q O – Q(

&(

)

*

8

/

<

9

;

&0

RSumber #okumentasi Pribadi >(0&/?

+ekerasan rataDrata

7 7 .7.

Standar de!iasi

= = ........7.

&8

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Standar de!iasi rataDrata

n

δ δ = =........7.

#b 7 n D & 7 &0 – & 7 ;

#engan nilai I 7 8 C maka nilai t tabel 7 t>I4(db? 7 t >........... ;? 7 ...............

2nter!al penduga kekerasan spesimen tanpa perlakuan panas.

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'ilimeter Block

8 &( cm

=ra"ik (.( ji Tanpa Perlakuan


$adi kekerasan rataDrata spesimen tanpa perlakuan panas berkisar antara

.. sampai .. dengan tingkat keyakinan ;8C

• #ata Spesimen dengan perlakuan panas

Tabel (./ #ata Spesimen dengan Perlakuan

:o. O O – Q O – Q(

&.

(.

).

*.

8.

/.

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;.

&0.

R


+ekerasan rataDrata

7 7 .7.

Standar de!iasi

= = ........7.

Standar de!iasi rataDrata

n

δ δ = =........7.

#b 7 nD& 7 &0 – & 7 ;

#engan nilai I 7 8C maka nilai t tabel 7 t>I4(db? 7 7 t > ......... ;? 7 ..........

2nter!al penduga kekerasan spesimen tanpa perlakuan panas

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'ilimeter Block

8 &( cm

=ra"ik (.( ji dengan Perlakuan


&

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$adi kekerasan rataDrata spesimen tanpa perlakuan panas berkisar antara

sampai dengan tingkat keyakinan ;8 C

• ji Beda #ua 3ata – 3ata

ntuk mengetahui ada tidaknya perbedaan kekerasan pada spesimen

tanpa perlakuan dan dengan perlakuan panas dilakukan uji beda dua rataD rata

dengan uji standart .

6ipotesa 6o & 7(

6& & N(

#igunakan pengujian dua arah dengan

I 7 8 C dan db 7 >n& – &? M > n( – & ?

7 > &0 – & ? M > &0 – & ? 7 &9

'aka nilai t tabel U t > ......... &9 ? 7 K ........

Perhitungan thitung

thitung 7 7

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+edudukan thitung pada kur!a distribusi t adalah sebagai berikut

&9

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'ilimeter Block

8 &( cm

=ra"ik (.* thitung pada kur!a distribusi t


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Kelompok 06

Pengujian Kekuatan Kejut

2.+ Pe),a%asan

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(0

= r a " i k ( . 8 6 u b u n g a n T i n g k a t + e k e r a s a n P e r l a k

u a n P a n a s d a n T a n p a P e r l a k u a n

=ra"ik -etak

&;.8 &&.8

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Kelompok 06

Pengujian Kekuatan Kejut.............................................................................................................................................

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2.- Kesimpulan dan Saran

2.-.1 Kesi)*u"an

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Kelompok 06

Pengujian Kekuatan Kejut.........................................................................................................................................

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1.-.2 Saan

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BAB III

PENGUJIAN KEKUATAN KEJUT

!.1 Tujuan Pengujian

&. 'engetahui daya tahan suatu logam terhadap beban dinamis yang menyebabkan

terjadinya patahan.

(. 'engetahui bentuk patahan.

). 'engetahui pengaruh perlakuan panas terhadap kekuatan kejut logam.

*. 'engetahui cara pengujian kekuatan kejut.

!.2 Definisi Kekua#an Keju#

((

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Kelompok 06

Pengujian Kekuatan Kejut+ekuatan +ejut > $pact test ? adalah kemampuan suatu bahan untuk

menahan beban dinamis atau mendadak yang dapat menyebabkan rusak atau patah.

$pact test merupakan suatu pengujian yang dilakukan untuk menguji daya tahan

suatu specien bila diberikan beban secara tibaDtiba melalui tumbukan yang

menyebabkan patah atau retak.

!.! Pe"aksanaan Pengujian

!.!.1 A"a# $an Ba%an &ang Digunakan

&. Charpy $pact Testing Machine.

#igunakan untuk mengukur kekuatan kejut.

Berat pendulum (* +g" 3adius lengan /0 cm

Sudut lengan ;0V

=ambar ).& Charpy $pact Testing MachineSumber Laboratorium Pengujian Bahan Teknik 'esin Fakultas Teknik ni!ersitas

Brawijaya >(0&/?

+eterangan =ambar

&. Pendulum.

(. Lengan pengikat

). $arum penunjuk der a jat

*. Pemutar lengan

8. Tuas sabuk r em

()

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Kelompok 06

Pengujian Kekuatan Kejut/. Sabuk r em

heating ?, penahanan >holding ?,

dan pendinginan >cooling ? dalam dapur. Seperti ditunjukkan pada gambar (.)

). Tang penjepit

#igunakan untuk mengambil benda uji dari dapur listrik pada proses perlakuan

panas. Seperti ditunjukkan pada gambar (.*.

*. Bak pendingin

#igunakan sebagai tempat media pendingin spesimen pada perlakuan panas%. Stopwatch

#igunakan untuk mengukur waktu holding. Seperti ditunjukkan pada gambar (.8

/. $angka Sorong

#igunakan untuk mengukur dimensi spesimen. Seperti ditunjukkan pada gambar

(.

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Kelompok 06



=ambar ).* =ra"ik Pergeseran Titik !utectoid



(8

:onsur

Paduan

+omposisi

>C?Suhu !utectoid C -

& - (

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Kelompok 06

Pengujian Kekuatan Kejut>L1'P231:?

!.!.2 P'se$u Pengujian



). Spesimen dipindahkan dari dapur listrik untuk proses pendinginan pada

media tertentu

*. Spesimen dibersihkan dari kotoran dan terak.

8. #ilakukan dry run test sebagai berikut

• Pendulum alat uji Charpy diatur agar benar – benar menggantung

bebas dan dalam keadaan diam.

• +edua jarum penunjuk diatur pada posisi !ertikal.

• Lengan pengikat diturunkan dengan roda pemutar.

• Tombol pengunci ditekan selanjutnya jika kedudukan lengan pengikat

sudah tepat terhadap pendulum, pengunci dapat dilepas tanpa menggesar

kedudukan pendulum.

• Pendulum beserta lengannya diangkat dengan roda pemutar sehingga

jarum luar menunjukkan skala yang sesuai dengan kedudukan pendulum

dalam posisi horiXontal >;0o?.

• #ilakukan dry run test untuk mengetahui energi yang dilepas mesin

karena kerugian mekanik. #ilakukan pencatatan sudut yang ditunjuk oleh

jarum.

/. #ilakukan pengujian sebagai berikut

• Spesimen diletakkan pada tempatnya sehingga bagian punggung takik

tepat pada posisi jatuhnya pendulum.

• #ilakukan pengujian seperti pada dry run test.

(/

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Kelompok 06


!.( Peng'"a%an Da#a

!.(.1 Da#a Ke"')*'k

Spesimen Tanpa Perlakuan

3adius lintasan > 3 ? 7 /00

Berat pendulum > = ? 7 (*

Luas penampang > F0 ? 7 /00

Sudut awal > Y ? 7 ;0

Sudut dry run > I0 ? 7 (Sudut akhir > I₁ ) 7 <

a. Anergi yang #iperlukan Secara 2deal

10 7 = 3 Zcos >;0V D I&0? – cos Y0[

7 (* /00 Zcos >;0V D

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Kelompok 06

Pengujian Kekuatan Kejutc. Anergi 1ktual yang #iperlukan

1 7 10 – "

7 & = ? 7 (*

Luas penampang > F 0 ? 7 /00

Sudut awal > Y ? 7 ;0

Sudut dry run > I0 ? 7 (

Sudut akhir > I₁ ) 7 9

a. Anergi yang #iperlukan Secara 2deal

10 7 = 3 Zcos >;0V D I&0? – cos Y0[

7 (* /00 Zcos >;0V D 9V? – cos ;0V[

7 &**00 Zcos 9(V – cos ;0V[

7 (00*,0; kg.mm

b. +erugian Anergi Pada 1lat

" 7 = 3 Zcos >;0V D I0V? – cos YV [

7 (* /00 Zcos >;0V D (V? – cos ;0V[

7 &**00 Zcos 99V – cos ;0V[

7 80(,88 kg.mm

c. Anergi 1ktual yang #iperlukan1 7 10 – "

7 (00*,0; – 80(,88

7 &80&,8* kg.mm

d. Anergi yang #iperlukan untuk 'ematahkan Spesimen Tiap Satuan Luas

Penampang.

1k 7 1 4 F0 7 &80&,8* kg.mm 4 /00 mm(

7 (,80( kg.mm 4 mm(

(9

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Kelompok 06


!.+ Pe),a%asan

(;

= r a

" i k

) . &

P e r

b a n

d i n

g a n

A n e

r g i

P a t

a h

d e n

g a n

T a n

p a P e r l

a k u

a n

d a n

P e r l

a k u

a n

P a n

a s

/ #

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Kelompok 06


Pada gra"ik ).& diatas dapat dilihat bahwa nilai energi patah pada perlakuan

panas /# dengan waktu holding /0 menit lebih besar daripada nilai energi patah

tanpa perlakuan. Pada perlakuan panas /#, energi aktual yang dibutuhkan untuk

mematahkan spesimen adalah (,80( kg.mm4mm(, sedangkan pada tanpa perlakuan

nilai energi patahnya sebesar (,09< kg.mm4mm(.

#ari gra"ik tersebut diambil kesimpulan bahwa gra"ik tidak mengalami

penyimpangan karena pada dasar teori dijelaskan bahwa perlakuan panas /#

memiliki nilai ipact strength yang paling tinggi. 6al ini disebabkan karena pada

perlakuan panas /# media pendinginnya adalah tungku dan waktu pendinginannya

lambat. #engan waktu pendinginan yang lambat menyebabkan ukuran butir bisa

berkembang maksimal. Semakin besar ukuran butir maka material akan bersi"at lebih

ulet sehingga menyebabkan nilai ipact strenght nya tinggi. Semakin ulet suatu

spesimen maka nilai ipact strengthnya tinggi dikarenakan penyerapan gayanya

bagus.

6omogenitas suatu material juga berpengaruh pada nilai ipact strength.

6omogenitas dalam hal ini adalah arah orientasi butir. Spesimen dengan perlakuan

panas /# cenderung lebih searah dalam arah orientasi butir, sehingga memiliki

energi patah yang lebih besar dibanding spesimen tanpa perlakuan. 6al ini sudah

sesuai dengan dasar teori bahwa semakin searah orientasi butirnya, maka ipact

strengthnya akan tinggi.

)0

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!.- Kesi)*u"an $an Saan

!.-.1 Kesi)*u"an&. :ilai energi patah pada perlakuan panas /# dengan waktu holding /0 menit lebih

besar daripada nilai energi patah tanpa perlakuan. Anergi patah pada spesimen /#

sebesar (,80( kg.mm4mm(, sedangkan energi patah pada spesimen tanpa

perlakuan sebesar (,09< kg.mm4mm(.

(. Semakin ulet spesimen maka nilai ipact strengthnya semakin tinggi karena

penyerapan gayanya bagus, sedangkan semakin getas suatu spesimen maka nilai

ipact strengthnnya semakin rendah.

). +euletan suatu spesimen dipengaruhi beberapa "aktor yaitu perlakuan panas padaspesimen dan media pendinginnya, waktu pendinginan, ukuran butir, dan juga

homogenitas.

!.-.2 Saan

&. 1latDalat untuk praktikum sebaiknya diperbaiki atau diganti karena sudah banyak

bagian yang mengalami kerusakan.

(. Sebaiknya pada pengujian ipact tidak hanya menggunakan pembebanan charpy.

). Seharusnya praktikan harus lebih teliti dalam mengambil data pengujian ipact

supaya tidak terjadi kesalahan.

*. $am untuk asistensi lebih diperpanjang supaya lebih maksimal.

)&

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Pengujian Kekuatan Tarik

BAB I

PENGUJIAN KEKUATAN TARIK

(.1 Tujuan Pengujian&. 'engetahui tegangan yield , tegangan ultiate, regangan dan kontraksi suatu

bahan.

(. 'engetahui pengaruh perlakuan panas terhadap parameter di atas.

). 'engetahui cara pengujian tarik.

(.2 Definisi Kekua#an Taik

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(.! Pe"aksanaan Pengujian

(.!.1 A"a# &ang Digunakan Da"a) Pengujian

&. 'esin ji Tarik

1lat ini digunakan untuk memberikan beban tarik kepada spesimen.

Spesi"ikasi 'esin ji Tarik

'erk 'FL Piu" – nd 'e Bysteme =mb6 # /900 'annheim

+apasitas &00 k:

Tipe P# &0

Tahun &;9(

'esin ini memiliki tiga skala pengukuran beban, yaitu

1 0 – (0 k:

1 M B 0 – 80 k:

1 M B M - 0 – &00 k:

+eterangan =ambar

&. Skala ukur pembebanan

(. $arum pembebanan

)(

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Pengujian Kekuatan Tarik). -rane pengunci "luida

*. -rane pengatur

kecepatan tar ik

8. -huck le!er

/. -huck

(0&/?

(. #apur listrik

#apur ini digunakan untuk proses pemanasan >heating ?, penahanan >holding ?,

dan pendinginan >cooling ? dalam dapur. Seperti ditunjukkan pada gambar (.).

). Tang penjepit

#igunakan untuk mengambil benda uji dari dapur listrik pada proses perlakuan

panas. Seperti ditunjukkan pada gambar (.*.

*. Bak pendingin

#igunakan sebagai tempat media pendingin spesimen pada perlakuan panas.

Seperti ditunjukkan pada gambar (.8.

8. Spidol

#igunakan untuk menandai spesimen.

=ambar *.( Spidol


Brawijaya >(0&/?

6. Stopwatch

))

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Pengujian Kekuatan Tarik#igunakan untuk mengukur waktu holding. Seperti ditunjukkan pada gambar

(.8.

St D )

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'ilimeter Block

&0 &0 cm

=ambar *.) =ra"ik Pegeseran Titik !utectoid



>L1'P231:?

(.!.2 P'se$u Pengujian



). Spesimen dipindahkan dari dapur listrik ke bejana pendingin untuk proses

pendinginan pada media tertentu

*. Spesimen dibersihkan dari kotoran dan terak.8. #ilakukan pengukuran dimensi spesimen, meliputi diameter awal dan panjang

awal. +emudian spesimen dibagi ke dalam segmen – segmen dengan panjang

masing – masing 8 mm.

/. Spesimen dipasang dengan erat pada alat uji.

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Kelompok 06

Pengujian Kekuatan Tarik;. Setelah patah, dilakukan pengukuran dimensi akhir spesimen.

(.( Peng'"a%an Da#a

(.(.1 Da#a Ke"')*'k

a. Spesimen Tanpa Perlakuan

Tabel *.( #ata 6asil Pengujian Spesimen

Tanpa Perlakuan

:o. \L

>mm?

#

>mm?

Beban

>k:?

&.

(.

).

*.

8.

/.mm?

Sesudah Patah >mm?


• +eterangan

- #iameter awal >#o? 7 .......

- #iameter "ltiate >#u? 7

- #iameter patah >#"? 7

- Beban &ield >Py? 7

- Beban "ltiate >Pu? 7

- Beban patah >P"? 7

- Panjang awal >lo? 7

)/

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- Panjang "ltiate >lu? 7

D Panjang akhir >l"? 7

• Perhitungan dan Pengolahan #ata

&. Luas Penampanga. Luas penampang awal >1o?

b. Luas penampang "ltiate >1u?

c. Luas penampang saat patah >1"?

.

(. 3egangan

a. 3egangan "ltiate rekayasa >ɛu?

b. 3egangan "ltiate sejati >ɛu]?

)

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..

..

c. 3egangan patah rekayasa >ɛ" ?

..

..

d. 3egangan patah Sejati >ɛ" ]?

..

..

..

e. 3egangan yield >ɛy?

..

..

..

). Tegangan

a. Tegangan "ltiate rekayasa >^u?

b. Tegangan "ltiate sejati >^u]?

)9

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Kelompok 06


c. Tegangan patah rekayasa >^"?

d. Tegangan patah Sejati >^"]?

e. Tegangan yield >^y?

*. +ontraksi >_?

8. 'odulus Alastisitas >A?

);

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Tabel *.* 6asil Pengolahan #ata Spesimen Tanpa Perlakuan

:o. Panjang

>mm?

Beban

>:?

#iameter

>mm?

Luas

>mm`?

Teg.

3ekayasa >:4mm`?

Teg.

Sejati>:4mm`?

3eg.

3ekayasa >C?

3eg.

Sejati >C?

+ontraksi

>C?

&.

(.

).

*.

8.

/.

mm?#

>mm?Beban>k:?

*0

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Kelompok 06


&.

(.

).

*.

8./.

mm?

Sesudah Patah

>mm?


• +eterangan

- #iameter awal >#o? 7 .......

- #iameter "ltiate >#u? 7

- #iameter patah >#"? 7

- Beban &ield >Py? 7

- Beban "ltiate >Pu? 7

- Beban patah >P"? 7

- Panjang awal >lo? 7

- Panjang "ltiate >lu? 7

D Panjang akhir >l"? 7

• Perhitungan dan Pengolahan #ata

&. Luas Penampang

a. Luas penampang awal >1o?

*&

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b. Luas penampang "ltiate >1u?

c. Luas penampang saat patah >1"?

.

(. 3egangan

a. 3egangan "ltiate rekayasa >ɛu?

b. 3egangan "ltiate sejati >ɛu]?

..

..

*(

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Pengujian Kekuatan Tarikc. 3egangan patah rekayasa >ɛ" ?

..

..

d. 3egangan patah Sejati >ɛ" ]?

..

..

..

e. 3egangan yield >ɛy?

..

..

). Tegangan

". Tegangan "ltiate rekayasa >^u?

g. Tegangan "ltiate sejati >^u]?

*)

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Pengujian Kekuatan Tarikh. Tegangan patah rekayasa >^"?

i. Tegangan patah Sejati >^"]?

j. Tegangan yield >^y?

*. +ontraksi >_?

8. 'odulus Alastisitas >A?

Tabel *.< 6asil Pengolahan #ata Spesimen #engan Perlakuan ....

:o. Panjang

>mm?

Beban

>:?

#iameter

>mm?

Luas

>mm(?

Teg.

3ekayasa

>:4 mm(

?

Teg.

sejati

>:4 mm(

?

3eg.

3ekayasa

>C?

3eg.

Sejati

>C?

+ontraksi

>C?

&.

**

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Kelompok 06

Pengujian Kekuatan Tarik(.

).

*.

8.

/.

3 e k a y a s a M s e j a t i ? D 3 e g a n g a n S

p e s i m e n j i t a n p a p e r l a k u a n

=ra"ik -etak

&;.8 &&.8 cm

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Pengujian Kekuatan Tarik.........................................................................................................................................

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B. =ra"ik 6ubungan Tegangan >rekayasa M Sejati? – 3egangan >rekayasa?

dengan Spesimen ji dengan Perlakuan ..

*< = r a " i k * . ( 6 u b u n g a n

T e g a n g a n > r e k a y a s a M S e j a t i ? – 3 e g a n g a n > r e k a y a s a ? d e n g a n S p e s i m e n j i P e r l a k u a n F .

=ra"ik -etak

&;.8 &&.8 cm

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.

-. =ra"ik 6ubungan 3egangan >rekayasa M Sejati? – +ontraksi dengan Spesimen

ji Tanpa perlakuan

*; = r a " i k * . ) 6 u b u n g a n

3 e g a n g a n > r e k a y a s a M S e j a t i ?

– + o n t r a k s i d e n g a n s p e s i m e n j i T a n p a p e r l a k u a n

=ra"ik -etak

&;.8 &&.8 cm

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.

#. =ra"ik 6ubungan 3egangan >rekayasa M Sejati? – +ontraksi dengan Spesimen

ji dengan Perlakuan ..

8& = r a " i k * . * 6 u b u n g a n

3 e g a n g a n > r e k a y a s a M S e j a t i ?

– + o n t r a k s i p a d a S p e s i m e n j i d e n g a n P e r l a k u a n F F F

=ra"ik -etak

&;.8 &&.8 cm

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8(

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.

A. =ra"ik 6ubungan Tegangan >rekayasa M Sejati? – +ontraksi dengan Spesimen

ji Tanpa Perlakuan

8) = r a " i k * . 8 6 u b u n g a n T e g a n g a n > r e k a y a s a M S e j a t i ?

– + o n t r a k s i p a d a S p e s i m e n j i T a n p a p e r l a k u a n

=ra"ik -etak

&;.8 &&.8 cm

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8*

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Pengujian Kekuatan TarikF. =ra"ik 6ubungan Tegangan >rekayasa M Sejati? – +ontraksi Spesimen

Perlakuan .

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88

= r a " i k * . / 6 u b u n g a n T e g a n g a n > r e k a y a s a M S e j a t i ? – + o n t r a

k s i p a d a S p e s i m e n j i d e n g a n

P e r l a k u a n F .

=ra"ik -etak

&;.8 &&.8 cm

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.

=. #iagram Pengukuran Besar #iameter Spesimen Sebelum dan Sesudah

Pengujian pada Spesimen Tanpa Perlakuan

8/ = r a " i k * . <

6 a s i l p e n g u k u r a n b e s a r d i a m e t e r s p e s i m e n s e b e l u m d a n s e s u d a h p

e n g u j i a n p a d a s p s e s i m e n t a n p

a

p e r l a k u a n

=ra"ik -etak

&;.8 &&.8 cm

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LAPORAN 06-1

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Transcript of LAPORAN 06-1