1.什么是坡口？

1. What is groove?

坡口的定义为：根据设计或工艺需要，将焊件的待焊部位加工成一定几何形状的沟槽称为坡口，那么我们平时见到的坡口有哪些样式呢？常用的坡口形式有I形坡口、Y型坡口、带钝边U形坡口、双Y形坡口、带钝边单边V形坡口等。

Groove is defined as: according to the design or process needs, the weldment to be welded into a certain geometry of the groove called groove, then we usually see the groove which style? The commonly used groove forms are i-groove, Y-groove, U-groove with blunt edge, double Y-groove, unilateral V-groove with blunt edge, etc.

2.焊接接头你了解吗？

2. Do you know about welded joint?

用焊接方法连接的接头称为焊接接头，它由焊缝、熔合区、热影响区及其邻近的母材组成。在焊接结构中焊接接头起两方面的作用。

The joint connected by welding is called welded joint, which is composed of weld, fusion zone, heat affected zone and its adjacent base metal. In welded structure, welded joint plays two roles.

一、是连接作用，即把两焊件连接成一个整体;

1、 It is the connection function, that is to connect the two weldments into a whole;

二、是传力作用，即传递焊件所承受的载荷。

2、 It is a force transfer function, that is, to transfer the load on the weldment.

3.焊缝的种类你知道多少？

3. What kind of weld do you know?

焊缝可分为对接焊缝、角焊缝、塞焊缝和端接焊缝四种。

Weld can be divided into butt weld, fillet weld, plug weld and end weld.

4.焊缝的宽度？

4. Width of weld?

指焊缝表面与母材的交界处称为焊趾。而单道焊缝横截面中，两焊趾之间的距离称为焊缝宽度

It refers to the junction between the weld surface and the base metal, which is called weld toe. In the cross section of single weld, the distance between two weld toes is called weld width

5.焊接应力产生的主要原因

5. Main causes of welding stress

(1）热应力。焊接过程对被焊工件来说，是局部的不均匀加热过程和不均匀冷却过程。这种不均匀冷热过程，会使工件中产生热应力。

(1) Thermal stress. The welding process is a local uneven heating process and uneven cooling process for the welded parts. This kind of uneven cold and hot process will cause thermal stress in the workpiece.

(2）拘束应力。由于构件本身或外加的刚性拘束作用，使焊接时热膨胀不畅，引起构件产生拘束应力。

(2) Restraint stress. Due to the rigid restraint effect of the component itself or the outside, the thermal expansion is not smooth during welding, resulting in restraint stress of the component.

(3）相变应力：焊接时，接头区域产生不均匀组织转变而引起的应力。

(3) Transformation stress: during welding, the stress caused by inhomogeneous microstructure transformation in the joint area.