This goes especially for playing tanks that don't have a taunt. I know standing in front of your carries is important, but what else can be done to protect them?
As a tank, you want to be a disruptive as much as possible. In lots of cases, simply zoning out their carries will let you win the teamfight. For example, one of my favorite tanks is Singed. I know I can use my slow to separate their team in a teamfight, activate poison to do a little damage to everyone, then run full speed at their carry. Their carry knows I have a fling, and generally my fling will put them out of position, so simply by running at them, I can force them out of the fight. If they are out of the fight, they are not hurting my team which is really the goal of a tank in a teamfight. In fact, I end up dealing more damage with my poison than they can do cause I make myself the only target they can attack.
These things ultimately depend on what your team needs you to do. I would not have chosen Singed if my team was playing protect the KogMaw, there are far better champs that can do that - Alistar, Galio, Janna, Nunu for example. But no, there are no way you can force the enemy to hit you in teamfights, but at same time, that isn't always your goal or shouldn't be. You want your team to do more damage than their team collectively. This simple statement usually determine who wins the teamfight.
This can change depending on which tank champion you are playing. Each tanks has abilities that let them bend the fight in a way. Getting all the damages are not always the priority.
The first thing to take in consideration is the "engage". Most of the time, in the rush of a team-fight, people will target the first champion which come. Either because they do not pay attention, or sometimes because they thing they can get him out fast. Other times, they are so afraid to let someone penetrates their rank that they won't challenge back lines by staying out of range. So be the one engaging is a first way to call a team to hit you.
The second thing is "Taunt" abilities (yes I will still talk about this). Remember that a lot of tank champions can do this. Rammus, Shen, Galio. It can be multi-target or single target. Taunting an enemy force him to attack you (usually they can't use skill as well). If you can get the carries to focus on you, you can release the pressure on your team-mates, allowing them to get these carries out first.
Third thing, is position control. When this won't make enemies target you, but put enemies in immediate danger. If you can grab an enemy into your formation, he's nearly sure to die. In another way, you can also push them back from the battlefield towards your lines.
Fourth, immobilisations. Some champions has the ability to stop enemy from moving (Maokai, Leona, ...). Using this on a melee champion basically let him only able to fight you if no one is near the root position. Eventually if you are forcing other enemies back, the one you got may be in big troubles. If the fight is static, global stun are also a great advantage. Once again, nobody is forced to attack you, but if you're playing Amumu for example, you could be sure they'll fear your AoE stun. This can be a great motivator to make them wanting to kill you fast (but they won't be able to).
Your objective as a tank is to sustain maximum of damages by :
- forcing people to attack you (skills)
- appealing the focus (using your threat level, being in the best position)
- breaking the enemy formation (grabs etc)
- breaking the fight structure (stuns, immobilisation)
If the enemies want to avoid you as much as possible, then you are a great asset for team-fights.