d*****i
发帖数: 213 | 1 具体的解释见下面的wiki
http://en.wikipedia.org/wiki/Motor_oil#Grades
但是，viscosity跟lubricity其实是两个概念。Lubricity的解释见下面wiki
http://en.wikipedia.org/wiki/Lubricity
这里面也提到lubricity的测量是按机械表面的磨损量来测定的。
This is done by determining how much wear is caused to a surface by a given
friction-inducing object in a given amount of time.
我想不明白的是为什么机油把粘度（比如5W-40）作为最重要的数字来做标号。 |
d*****i
发帖数: 213 | 2 按照下面的解释，viscosity的意义仅在于让机油在高温时仍然黏在金属表面上，但跟
lubricity并没有直接关系。那么也就是说我们买机油用来参考的标号其实完全不对应
机油的润滑性能？
那么机油的润滑性能能通过什么方式查到吗？
http://in.answers.yahoo.com/question/index?qid=20110609104051AA
Viscosity is just the thickness of the lubricant. You could have a lubricant
like grease mixed with solid lard and have a very high viscosity, but the
lard would actually reduce the lubricity.
The lubricity just refers to the actual slipperiness of the lubricant. You
could have a solid lubricant like lithium or graphite and it basically can't
be measured for viscosity, but yet it has excellent lubricity
In motor oils, high viscosity only aids in making the lubricant adhere to
metal parts better at higher temperatures, but it doesn't actually increase
the lubricity
given
【在 d*****i 的大作中提到】
: 具体的解释见下面的wiki
: http://en.wikipedia.org/wiki/Motor_oil#Grades
: 但是，viscosity跟lubricity其实是两个概念。Lubricity的解释见下面wiki
: http://en.wikipedia.org/wiki/Lubricity
: 这里面也提到lubricity的测量是按机械表面的磨损量来测定的。
: This is done by determining how much wear is caused to a surface by a given
: friction-inducing object in a given amount of time.
: 我想不明白的是为什么机油把粘度（比如5W-40）作为最重要的数字来做标号。
|
d*****i
发帖数: 213 | 3 ?
given
【在 d*****i 的大作中提到】
: 具体的解释见下面的wiki
: http://en.wikipedia.org/wiki/Motor_oil#Grades
: 但是，viscosity跟lubricity其实是两个概念。Lubricity的解释见下面wiki
: http://en.wikipedia.org/wiki/Lubricity
: 这里面也提到lubricity的测量是按机械表面的磨损量来测定的。
: This is done by determining how much wear is caused to a surface by a given
: friction-inducing object in a given amount of time.
: 我想不明白的是为什么机油把粘度（比如5W-40）作为最重要的数字来做标号。
|
