(一)(A)
the hardness of a metal is its resistance to surface indentation under standard test conditions.two main test methods are used: Brinell, Rockwell
金属的硬度是抵抗表面压痕试验的能力。. 两种主要试验方法下使用:布氏,洛氏 The Brinell Test
布氏硬度试验
The Brinell test (Fig.2-3) is mainly used for materials whose thickness is 0.25 in. or greater. The testing technique is to impress a 10-mm diameter hardened steel
布氏硬度(fig.2-3)主要用于材料的厚度为0.25。或更大。测试技术是给一个直径10毫米的硬化钢
ball into the surface of the material under 3000 Kg load for 15~60 sec. A smaller load is used when testing softer metals and alloys. The diameter, in millimeters, of
球到表面的材料3000公斤载荷下15 ~ 60秒。一个较小的负载进行测试时,较软的金属和合金。在毫米直径的,
the dent made by the ball is measured by a microscope, and the area is calculated. 由球处用显微镜测量,和面积计算。
The brinell hardness number (HBS) may be calculated from the formula
布氏硬度值(HBS )可由公式计算
HBS=
HBS =
Where D = ball diameter (mm)
其中d =球直径(mm )
d = diameter of circular indentation (mm)
a 圆形压痕直径(mm )
F = load, which, in hardness testing, has units of kilogramme-force where 1 kgf = 9.8 N F =负载,其中,硬度测试,具有千克力在1公斤= 9.8 N单位
However, to avoid this tedious calculation, the Brinell hardness number may be found from tables relating hardness to the diameter of the indentation. Each table of
然而,为了避免这种繁琐的计算,布氏硬度值可以从有关硬度的压痕直径表。每个表 such relationships refers to a specific load and ball diameter.
这种关系是指一个特定的负载和球径。
The Rockwell Test
洛氏的试验
In the Rockwell test (Fig.2-4) the depth of the indentation is measured by the instrument and this is directly indicated on a dial as a hardness value. No subsequent
在洛氏试验(Fig.2-4)压痕的深度是由仪器,这是直接在拨号作为硬度值表示测量。没有后续的
measurement of the indentation is involved.
压痕的测量涉及。
The test-piece is placed on the table of the machine and the indenter is brought into contact with the prepared surface under a minor load of 10 kgf. This takes up the 试件置于机表和压头被带入与制备的表面接触的小负荷下的10公斤。这需要了
‘slack ’ in the system and the dial indicator is set to zero. The major (additional) load is then applied, and when the reading of the major load is taken off. The
“松弛”的体系和百分表设置为零。主要的(额外的)负载的应用,当主要的负载读取下。的
test-piece remains under the minor load while the hardness value is read directly from the dial indicator. Nine scales of hardness are available (A to K inclusive) but
试件仍然是小负荷下,硬度值是从百分表直接读取。九硬度范围是可用的(一个K 含)但 the most commonly used are the B and C scales, the details of which are given in table 2-1.
最常用的是B 和C 的尺度,其中的细节表2-1给出。
The Dial is divided into 100 divisions, each representing one point on the hardness scale. The symbol HR is supplemented by a letter (e. g. B or C) which denotes the
表盘是分成100个级别,每个代表在硬度表一点。符号HR 补充一个字母(如B 或C )是 particular hardness scale used. The Rockwell test is particularly suitable for rapid routine checks on finished material. The C scale is used mainly for hardened
特别是硬度表。洛氏测试的特别适合于快速的日常检查成品。C 表主要用于硬化
steels, while the B scale is used for unhardened steels and the harder non-ferrous alloys. 钢,而B 的比例用于未淬火的钢和有色合金。
(B )
(一)(A)
the hardness of a metal is its resistance to surface indentation under standard test conditions.two main test methods are used: Brinell, Rockwell
金属的硬度是抵抗表面压痕试验的能力。. 两种主要试验方法下使用:布氏,洛氏 The Brinell Test
布氏硬度试验
The Brinell test (Fig.2-3) is mainly used for materials whose thickness is 0.25 in. or greater. The testing technique is to impress a 10-mm diameter hardened steel
布氏硬度(fig.2-3)主要用于材料的厚度为0.25。或更大。测试技术是给一个直径10毫米的硬化钢
ball into the surface of the material under 3000 Kg load for 15~60 sec. A smaller load is used when testing softer metals and alloys. The diameter, in millimeters, of
球到表面的材料3000公斤载荷下15 ~ 60秒。一个较小的负载进行测试时,较软的金属和合金。在毫米直径的,
the dent made by the ball is measured by a microscope, and the area is calculated. 由球处用显微镜测量,和面积计算。
The brinell hardness number (HBS) may be calculated from the formula
布氏硬度值(HBS )可由公式计算
HBS=
HBS =
Where D = ball diameter (mm)
其中d =球直径(mm )
d = diameter of circular indentation (mm)
a 圆形压痕直径(mm )
F = load, which, in hardness testing, has units of kilogramme-force where 1 kgf = 9.8 N F =负载,其中,硬度测试,具有千克力在1公斤= 9.8 N单位
However, to avoid this tedious calculation, the Brinell hardness number may be found from tables relating hardness to the diameter of the indentation. Each table of
然而,为了避免这种繁琐的计算,布氏硬度值可以从有关硬度的压痕直径表。每个表 such relationships refers to a specific load and ball diameter.
这种关系是指一个特定的负载和球径。
The Rockwell Test
洛氏的试验
In the Rockwell test (Fig.2-4) the depth of the indentation is measured by the instrument and this is directly indicated on a dial as a hardness value. No subsequent
在洛氏试验(Fig.2-4)压痕的深度是由仪器,这是直接在拨号作为硬度值表示测量。没有后续的
measurement of the indentation is involved.
压痕的测量涉及。
The test-piece is placed on the table of the machine and the indenter is brought into contact with the prepared surface under a minor load of 10 kgf. This takes up the 试件置于机表和压头被带入与制备的表面接触的小负荷下的10公斤。这需要了
‘slack ’ in the system and the dial indicator is set to zero. The major (additional) load is then applied, and when the reading of the major load is taken off. The
“松弛”的体系和百分表设置为零。主要的(额外的)负载的应用,当主要的负载读取下。的
test-piece remains under the minor load while the hardness value is read directly from the dial indicator. Nine scales of hardness are available (A to K inclusive) but
试件仍然是小负荷下,硬度值是从百分表直接读取。九硬度范围是可用的(一个K 含)但 the most commonly used are the B and C scales, the details of which are given in table 2-1.
最常用的是B 和C 的尺度,其中的细节表2-1给出。
The Dial is divided into 100 divisions, each representing one point on the hardness scale. The symbol HR is supplemented by a letter (e. g. B or C) which denotes the
表盘是分成100个级别,每个代表在硬度表一点。符号HR 补充一个字母(如B 或C )是 particular hardness scale used. The Rockwell test is particularly suitable for rapid routine checks on finished material. The C scale is used mainly for hardened
特别是硬度表。洛氏测试的特别适合于快速的日常检查成品。C 表主要用于硬化
steels, while the B scale is used for unhardened steels and the harder non-ferrous alloys. 钢,而B 的比例用于未淬火的钢和有色合金。
(B )