# Lab Report 1

July 8, 2017 | Author: yuwaraja | Category: Hardness, Mechanical Engineering, Materials, Building Engineering, Materials Science

#### Short Description

material science...

#### Description

LAB REPORT

GROUP MEMBER YUWARAJA A/L SAMY

08DKM15F2004

INTAN AYU WIRDANI BINTI MOHD AZAM 08dkm15f2018 FATIN NUR AQILAH BINTI MASHAR

08dkm15f2007

Satish a/l sekhar Jeevanraj a/l parameswaran

08dkm15f2040 o8dkm15f2039

COURSE CODE DJJ 3213 Material Science

TITLE

Hardness Test (Vickers Hardness Test)

LAB.NO.

DJJ DKM/LS/2.2(01)

CLO: At the end of this experiment, the student should be able to determine material hardness. Experiment Outcomes: The outcomes of this lab are to introduce the student to the topic of the indentation hardness of metals using the common hardness test and scales. These sets of test on metals of widely different hardness show: 1. The empirical interrelationship between the various hardness scales. 2. The relationship for a given scale as a function of applied load. 3. The relationship between hardness and tensile properties.

Objectives: The objective of this experiment is to determine the hardness of a material by using a hardness tester. Safety precaution: a) Make sure the student follows the laboratory or workshop safety regulators. b) Experiment must be conducted by lecturers or experienced lab assistance. c) Always know the hazards associated with the materials that are being utilized in the lab. d) Always wear appropriate clothing. e) Never perform an authorized work , preparations or experiments. f) Be familiar with the location of the emergency equipment

Apparatus:

1. Vickers hardness testing equipment, similar to the model shown. 2. Material Samples, Copper and Steel.

vickers

Theory: Vickers hardness test conducted by the test surface with diamond-based pyramid eye square. Vickers hardness can be defined as the value calculated according to the formula below: Hv=

=

P D2 / (2sinØ/2)

=

2P sin 680 D2

=

1.8544P D2 HV = Vickers hardness number

0 = angle of the pyramid indenter 136 P = load test (kgf) D = the average of the diagonal (mm) Note: does not have numerical value Hv units. Example: 150Hv / 30 Vickers hardness test is a test that can give OVERVIEW hardness suitable for soft material so that the material is harder, ie it is suitable for testing the hardness of the material has a large range, especially steel very hard. Load consumption by ordinary materials is as table 1 Material steel and cast iron copper alloy pure copper, aluminums alloy Pure aluminium lead, tin and tin alloys

Load (KG) 30 10 5 2.5 1

Procedure: The hardness tests are carried out under the supervision of the lab instructor. General procedure: 1. The specimen was placed on the vice. 2. The indenter was lowered until it just touches the specimen surface. 3. The appropriate load (F = 10kgf) was set for the indenter for 10 seconds. 4. The indenter was allowed to penetrate the specimen surface. 5. Load was removed and indenter was raised from specimen surface. 6. The appropriate parameter (diameter) of the indentation was measured. 7. The hardness value was computed. 8. The above steps were repeated for 2 times at different locations on the specimen and the average value was computed.

Result: Material

Copper Copper Copper

20KG 20KG 20KG

Material

249.8 248.0 239.1

D1 Steel steel steel

20KG 20KG 20KG

283.7 282.0 282.4

Microscope Reading D2 D=(D1+D2)/ 250.6 249.4 240.3

2 250.2 248.4 239.7 Average

HV Machine Calculatio 592 599 645

n 5.92 X 10-4 6.01 X 10-4 6.46 X 10-4

HV Machine Calculatio

2 283.1 281.85 284.75 Average

n 4.63 x 10-4 4.67 x 10-4 4.57 x 10-4

282.5 281.7 287.1

463 467 457

Discussion 1. Draw a curve shape us can see the position of the measuring

2. Provide major advantages of Vickers hardness test hardness test compared with other The main advantage of the Vickers method consists in employing only one scale, that can range from the lowest to the highest hardness. For this reason this method is fundamental for researching laboratories. Any deformation of the indentation may reveal structural characteristics of the test material. As for the Brinell test, the Vickers method is not sensitive to any deflection of the work piece. In comparison with the Rockwell and Brinell values, the Vickers hardness number has a proper meaning, as it represents a specific load on an indentation having always the same shape. 

The Vickers method can be used with any and all materials and test specimens, from soft to hard, as the procedure covers the entire hardness range.

There is only one type of indenter, which can be used for all Vickers methods.

Non-destructive testing is possible, so the test specimen can be used for other purposes.